Fuel Pressure input

[Beer99C5]

I was hoping to add fuel pressure as a PID, was planning on a dynotune gauge but they said it would not work (I guess its not based on a 4.8-5.0 V signal???).

Anyone successfully do this? If so what gauge was used?

Beer

[Beer99C5]

Found it at the innovate boards...:muahaha:

Autometer's electric full sweep fuel pressure gauge is 0-5V linear. You could probably buy just the sender from them if you don't want the gauge.

That's what I am using for fuel pressure data logging. Tap into the purple wire in the harness to get the signal. According to Autometer, the sender is calibrated to .5V at 0 psi and 4.5V at 100 psi, with a linear scale.


Here is a link to the sending unit
http://www.autometer.com/cat_accessoriesdetail.aspx?vid=27

Now I wonder how hard it would be to make a harness for it? $100 beats the $250 for the entire gauge kit...

:)

[Redline Motorsports]

Hey this looks cool! I am looking for a setup like this for our dyno! It also will take a 0-5 volt device!

[Beer99C5]

The Wiring harness for the Sending unit is availible directly from Autometer its $25. Here is the number to them.

That sender operates based on a 5v input, a chassis ground, and a
return signal based on pressure. 0.5v = 0 psi, and 4.5v = 100 psi. This
is a linear signal.
You may purchase a harness through our Service Department at
815-899-0801. The cost is $25.00.
Thank you.
Cory
Tech/Service

[TAQuickness]

did you get the sender direct from autometer?

[Beer99C5]

Got it from Summitracing it should be on the brown truck somewhere...
http://store.summitracing.com/partdetail.asp?autofilter=1&part=ATM%2D2246&N=115&autoview=sku Sending unit only


Wow...I just called Autometer for the harness, and they are sending it for nuthing...They asked what gauge I was running and I told them my intentions (no gauge just to use for logging...) and they said they would send out the harness right away...

Pinch me! Am I dreaming?

[TAQuickness]

I wasn't so lucky. Autometer gave me this part number (http://store.summitracing.com/egnsearch.asp?Ntt=5223&N=115+400442&Ntk=KeywordSearch) and it cost $35. Still beats $250 for the guage.

Thanks for posting this up Beer. Be sure to document your install and I'll help you proof it when I install mine.

[Beer99C5]

I hope the Fuel pressure thing works out as I am having ZERO luck with my LC-1 wideband...

0 volts on warmup (correct) then when warm 2 volts, then a minute later 5 volts...and a 8 code. Changed the sensor, made a heat sink, recalibrated the heater, free air recal, still no worky. Try and program the LC-1 and it won't connect to the serial port unless I use the out line to the LC-1 :bash:

[Happy Jim]

Try and program the LC-1 and it won't connect to the serial port unless I use the out line to the LC-1 :bash:

?? the "out" line is the one you are supposed to connect to your PC for programming, the "in" line should have a terminator plug inserted into it (unless you are running multiple LC1's).

Jim

[Beer99C5]

From the Dynotune instructions...

Please read the LC-1 controller handbook cover to cover so you understand the principles of operation.
1) Connect your laptops program cable to the “IN” connector on the
LC-1.
2) Launch the Innovate Configuration Software. A small box will pop up asking “make sure the LC-1 is connected”.
3) Now turn the key to the “on” position so the LC-1 has power. The configuration software screen will automatically pop up on the screen. You are now ready to configure the LC-1.
Set the parameters as follows:
1) Verify that the fuel setting is gasoline and set at 14.7
2) Click on the “analog output 1” tab.
3) Set analog output 1 as follows:
a. Select the “air fuel ratio” button
b. 1.000V= 10.00 a/f
c. 2.000V= 20.00 a/f
d. Select “advanced” button
e. Select the “Instant” sample rate.
f. Enter 0.00V at warm up.
g. Enter 5.00V at output error.
h. Press “OK”
i. Press the program Button. It takes one second to program, you will not get any message about programming completed but you will notice that the program button is now shaded. This confirms that you have programmed the LC-1.
j. You are done!


But hey I am willing to try anything, I am waiting on a RMA # and instructions and don't really want to cut the thing out...

[joecar]

From the Dynotune instructions...

Please read the LC-1 controller handbook cover to cover so you understand the principles of operation.
1) Connect your laptops program cable to the “IN” connector on the LC-1.
...
That's incorrect, see section 5.3 in the Innovate LC-1 manual
(it says to connect the terminator plug into the "IN" connector):

http://www.innovatemotorsports.com/support/manual/LC-1_Manual.pdf

[Beer99C5]

Waiting on the harness...

http://www.retrorelics.net/jim/Boards/Corvette/FuelpresSunit.JPG

http://www.retrorelics.net/jim/Boards/Corvette/FuelpresSunit2.JPG

I think this is where I should be looking...
What I hope to do is use the Wideband AFR 2 (AFR_LC12) and edit the sae_generic.txt file to something like this?


V 0.5 4.8 .1 "{EXT.AD2}"
AFR 0.0 100.0 .1 "{EXT.AD2}*10"
*CLC-00-931
factor 0.0 2.0 .1 "{CALC.AFR_LM12.AFR}/{GM.AFR}"

On the LC-1 I agree to log to Logworks2 you need to connect to the out line.
I beleive to program the LC-1 you must connect to the In Line...

Innovate gave me a RMA, so hopefully it will work when I get it back.

[TAQuickness]

Just checked the front porch... Summit is fast. Got the sender, wire harness, and they threw in a hat and catalog. Not too shabby.

As for the wiring, I suppose the red is +12, black is ground, and purple is the signal? Also, Beer, where did you get your fittings?

[Beer99C5]

Ahh man, you got a free hat? My harness is coming from Autometer, the sending unit I got from Summit (they forgot my hat though:nixweiss: )

Yes purple is the signal.

The fittings I got from Summit, -4 swivel is the blue one, then a -4 to a 1/8NPT

LOL you'll have it working before me..tag you do the tutorial :)

[TAQuickness]

If I have to order fittings, I bet you beat me to it. I think I might be able to dig some up at work.

The hat is nice too.

[Beer99C5]

Got the harness, made a spreadsheet to compare the autometer Volts to FP (since I will not be running a gauge.

http://www.retrorelics.net/jim/Boards/EFILive/autometerFPgauge.xls

Should be messing with it today...

[TAQuickness]

I've had 0 luck finding the fitting's locally.

Nice spreadsheet. Where did you get the 0.5 - 4.5 vdc? I was under the impression the transducer was 0-5 vdc.

[Beer99C5]

From an Email from their tech support.

Hello.

That sender operates based on a 5v input, a chassis ground, and a
return signal based on pressure. 0.5v = 0 psi, and 4.5v = 100 psi. This
is a linear signal.
You may purchase a harness through our Service Department at
815-899-0801. The cost is $25.00.
Thank you.
Cory
Tech/Service

[TAQuickness]

I need some coffee... Thanks for posting that again.

[Beer99C5]

LOL ok I have it all in...what do I do now?
Am I on the right track with changing one of the wideband's file to reflect the above Voltage/pressures?

V 0.5 4.5 .1 "{EXT.AD2}"
PSI 0.0 100.0 .1 "{EXT.AD2}"
*CLC-00-951

Not sure what this does...

factor 0.0 2.0 .1

TA hit me up on Yahoo mess.if ya can

[Beer99C5]

Well basic monitoring of the V did not pan out to well...

Grey wire 12 V switched
Black Ground
Purple output...

Showing 1.45-1.47 Volts (at the sensor and in EFI at the EXT.AD2) which equates to 24-26 PSI...expecting to see 2.8 V + or -
Mechanical gauge shows 60 PSI on the same T.

No sense in trying to add it to the PIDs if the math is not working out...

:frown:

[TAQuickness]

LOL ok I have it all in...what do I do now?
Am I on the right track with changing one of the wideband's file to reflect the above Voltage/pressures?

V 0.5 4.5 .1 "{EXT.AD2}"
PSI 0.0 100.0 .1 "{EXT.AD2}"
*CLC-00-951

Not sure what this does...

factor 0.0 2.0 .1

TA hit me up on Yahoo mess.if ya can


I would just create a new PID in the user file. If you modify one of the PID's in the SAEGeneric file, it will be overwritten with software updates.

Have you tried hooking the sender directly to the end of the rail? Perhaps the sender is not getting a true reading.

[Beer99C5]

Relocated at the fuel rail and still 1.4 V...which is 1/2 the 2.8 I am looking for...I am wondering if the gauge (which I do not have does something like multiply the output say by x 2 when its connected?).

Have a email into tech support, don't expect an answer til Monday.

[Beer99C5]

Here is what I got from Tech support...
So the gauge does step the voltage down...
So How do I find a 5 Volt power source :nixweiss: everything is 12 volt on the car?

Hmmm maybe the ETC???

From Tech Support

No the wiring is not correct you should have a +5 volt power source to
the gray wire and signal and ground are right. I think the higher input
voltage is affecting the output voltage.

[TAQuickness]

all you need is a resistor to drop your voltage. Might also check your EGR wiring for a 5vdc source.

edit:
I don't have my resistor calculations handy, but it truely is a cheap fix.

[TAQuickness]

If my figuring is correct, you will need a resitor 1.4 times the resistance of the sender.

[emarkay]

Be careful of resistors near fuel - if you don't get the right wattage they can get real hot, and are not always stable for voltage dropping purposes.

Short on time here, but are you trying to drop DC voltage (say 14VDC to 5VDC?)

Those 78xx / 79xx voltage regulators are the niftyest things for this, are less than a dollar, and are good for an amp if heatsinked!

http://www.fairchildsemi.com/pf/LM/LM7809.html

I use a one to get 9VDC for my MP3 player.

[TAQuickness]

thanks mark

[ringram]

5v goes down the stock NB02 wires... maybe you can splice into that on one side. Its a switched source. Trace it back nearer the source and off you go.

[TAQuickness]

ringram - which wires? I've measured 12vdc across the heaters and 0-1 with the NB hooked up. Looking at the schematic, and I don't see where 5vdc would come into play. Help!

[TAQuickness]

ahh!! but it does look like the gray wire on the EGR (2000 Fbod) has a 5vdc reference.

[TAQuickness]

if you are looking at the EGR connector, in order left to right, wiring facing you, you have gray, black, brown, gray, and red. The gray wire closest to the red wire has 5vdc. Just verified it with the ohm meter.

[TAQuickness]

well I'll be a post whore...

[TAQuickness]

whore it one more time for an even 873 :D

From the blue connector on the PCM:

2000 Fbody:
Pin 45, GRA, circuit 474, A/C Refrigerant Pressure Sensor 5V Reference

Pin 46, GRA, circuit 474, Fuel Tank Pressure Sensor 5V Reference

Pin 47, GRA, circuit 416, EGR Pintle Position Sensor 5V Reference

Pin 48, GRA, circuit 416, MAP Sensor 5V Reference


1999 C5:
Pin 45, GRY, circuit 474, A/C Refrigerant Pressure Sensor 5V Reference

Pin 46, GRY, circuit 598, Fuel Tank Pressure Sensor 5V Reference

Pin 47, --, --, Not Used

Pin 48, GRY, circuit 416, MAP Sensor 5V Reference

[joecar]

Cool, there's 5V sources all over the place... 8-) :cheers:

[emarkay]

Just be careful - if you are tapping into a "REFERENCE" signal, any perturbations (noise) or other poo-poo added to the line may cause what's expecting a crystal clean reference voltage to start having grand mal seizures.

I'd still make an isolated 5V source IMHO. Believe me, I have seen noise you can't even see with a 'scope send digitial timing circuits into fits, and down the line, some bizarre waveforms (and FYI, at least you will know where the noise source is, but, tracking back to locate an unknown source of buss noise is a job for those with Jolt Cola IV's and no social life...) ( Ok, so I saw this in the 80's, but yea, it's still true...) :)

MRK

[Beer99C5]

Going in with the 5V Regulator from Radio Shack...

That don't work I will try the green wire on the ETC...

:cheers:

[Beer99C5]

Well I am pretty frustrated.

I have 4.97 Volts using a Radio Shack 5V regulator to the sending unit and it is now recording .3 to .4 with a mean of .36 which is no where near where it is supposed to be. A mechanical gauge on the T shows a solid 60 PSI.

I hope TAQ's goes better than my progress.

[DrX]

I am logging the voltage OK off the purple wire(I have the gauge which provides the 5V source) but having trouble with creating the calc PID for FP. First stab at the process. Thought I had it but I get something like "Units PSI not found" error message. Tried adding PSI under *Units in cac_pids.txt but then I get a "duplicate" error message. Must be missing something. Read everything I could find on creating PIDs. Let me know when someone gets it worked out.

[TAQuickness]

DrX - Can you verify the voltage between the guage and sender is 5vdc?

[DrX]

DrX - Can you verify the voltage between the guage and sender is 5vdc?

Yes, I confirmed that when I did the hookup to the Flashscan yesterday. Grey wire was just under 5V. Logged output from the sender averaged 2.5V. 2.74V at a MAP of 160 kPa(boost referenced).

[TAQuickness]

cool. Need to get my manifold issues worked out so I can free up one of my A/D's (really just need to get V2)

[TAQuickness]

I sent the FP signal thru the EGR. Install looks stock.

Beer99C5 - You're gonna need the following in your calc_pids.txt file

I've attached a text file with the same data.


*UNITS

#Code System Abbr Description
#-------- ---------- -------- -------------------------------------------------------------

PSI Imperial PSI "Pounds Per Square Inch"
# ================================================== ============================
# Add slot definitions here
# --------------------------------
# See sae_generic.txt for more information on "SLOT" formats
#
#Units Low High Fmt Expression
#------------ ------------- ------------- ---- --------------------------------------------------------------
*CLC-00-001
PSI 0.00 100.00 .2 "({EXT.AD1}*25)-12.5"

# ================================================== ============================
*PRN - Parameter Reference Numbers
# --------------------------------
# See sae_generic.txt for more information on the *PRN section
#
#Code PRN SLOT Units System Description
#------------------------- ---- ------------ ---------------- ---------------- ------------------------------------------
CALC.FP F001 CLC-00-001 PSI Fuel "Fuel Pressure"

I'll start writing up a tutorial in the near future.

[Beer99C5]

Excellent! I get home in September and will give it a go and get it right this time :bash: . LOL hope the thread keeps guys from making the same mistakes I did.

At least I have EFI Scan here on the ship on my laptop so I can play around with it (and add your stuff to it) :beer:

[TAQuickness]

take a look in the lounge at my FAST90 woe's thread. I've posted some logs that you can use the new calc.pid with.

[DrX]

Does your FP plot look like mine? The gauge doesn't bounce around like this.

[TAQuickness]

yes. under steady state conditions i have a +- 2psi swing in pressure. Can't post it now, but I took a log during lunch and found my pressure drops to 55 psi at WOT.

[TAQuickness]

-4AN to 1/8 NPT fitting required for fuel pressure sender install (http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3865991416&rd=1&sspagename=STRK%3AMEWN%3AIT&rd=1)

[Tordne]

Received all my stuff for this today :). Now I just have to decide whether to wired direct to FlashScan or take over the EGR portion of the PCM.

[ringram]

Where is the info for EGR wiring?

Hey Tordne, did you stick your thermal blanket on? Does it fit well?

[TAQuickness]

Where is the info for EGR wiring?

Hey Tordne, did you stick your thermal blanket on? Does it fit well?


I wrote a tutorial for this. It's still out for proofing. If you are interested, send me your email address and I'll send you an early copy. If not I should be publicly available in the next few days.

[Tordne]

Where is the info for EGR wiring?

Hey Tordne, did you stick your thermal blanket on? Does it fit well?

Not yet mate. Will probably be a weekend job :)

[joecar]

Thermal blanket... to keep your headers hot...? :)

[Tordne]

Thermal blanket to put between OTRCAI and radiator to reduce heat soak into the intake. I ordered it with my fuel pressure stuff from Summit so this was a "may as well" item given that I was paying the shipping and handling charges anyway :)

[TAQuickness]

how's the FP install going?

[Tordne]

Going to leave it for the weekend when I have some time :) I also need to try and find one of those valve removal tools.

[TAQuickness]

you can get them at any tire shop, wal-mart, autoparts store, etc... Even a small pair of needle nose pliers will work

[Beer99C5]

I will be trying again this Friday along with my LC-1. Autometer sent me a new sending unit (@ no cost) despite me putting 12V to it instead of 5V (yes I told them what I did) :rockon:

I love customer service like that. They gained my business for gauges for my 73 Charger when I get around to putting that together (tach and misc gauges).

[TAQuickness]

very cool. let us know how it goes

[Beer99C5]

Autometer did replace the one I fried for nuthin,
Voltage is right @ 2.93 @ 60psi, will connect it to EFI live when I get the LC-1 in...will take some pics for ya TA and send them to ya mostly the 5V regulator I guess and maybe the sensor off the noid. Most questions will be "what fittings do I need...???" we did it different ways.

Other than the "Pressu" issue I encountered, tutorial was excellent.

On to the pesky LC-1.

[ace68]

thanks TAQUICKNESS your tutorial made installing this so easy.

[jsttry]

Any update on the tutorial? Are you able to send me a copy pls?

[joecar]

Any update on the tutorial? Are you able to send me a copy pls?jsttry,

Is this what you need (see post #1): showthread.php?t=3661 (http://forum.efilive.com/showthread.php?t=3661)

Cheers
Joe
:cheers:

[TAQuickness]

jsttry,

Is this what you need (see post #1): showthread.php?t=3661 (http://forum.efilive.com/showthread.php?t=3661)

Cheers
Joe
:cheers:


:D:cheers: :D

[jsttry]

Yep, perfect, thank you :D

[Ken G]

Thanks for the tutorial, TAQuickness! :master:

I already had the Autometer Nexus gauge setup and figured that it would be very easy to just tap into the signal wire to provide the external input for my FlashScan cable but I didn't know how to convert that voltage into a calculated fuel pressure PID. Your write up made it a breeze. I added the PID, tapped the wire, and had my first scanned data in about 30 minutes (couldn't have been easier). I also made an RPM v. MAP map to track my fuel pressure "in boost". The more I use EFILive and read this forum, the more I love this product!

-Ken

[redhardsupra]

hey, could you post that rpm vs map vs boost log?

[Ken G]

hey, could you post that rpm vs map vs boost log?

Here's a little bit of data that I collected with relatively low boost. I'm running COS 3 with a 2-bar sensor. BTW, I use your IFR spreadsheet and it has been invaluable.

Thanks, Ken

http://ktgutz.home.comcast.net/fp.png

[TAQuickness]

Welcome to the forum Ken!

I notice you get a few dips in your fuel pressure as well. If you don't mind, would you send a copy of that log to TAQuickness at Houston dot RR dot Com?

Is it safe to assume your gauge does not indicate as low as the scanned values?

[Ken G]

Welcome to the forum Ken!

I notice you get a few dips in your fuel pressure as well. If you don't mind, would you send a copy of that log to TAQuickness at Houston dot RR dot Com?

Is it safe to assume your gauge does not indicate as low as the scanned values?

I'll send you the log right now. The gauge lags the logged data in real time. The Nexus gauges do allow you to record and playback data in a stepwise fashion and the dips are easily seen then. I am running an MSD pump booster on an '04 FFS fuel system. I don't have plans to go over my current 7-8 PSI of boost so I'm hoping I can get away without a major fuel system upgrade. BTW, I do run an ECS/Alky Control methanol injection pump.

Thanks, Ken

[TAQuickness]

Ken - Do you have a boost referenced regulator?

[Ken G]

Ken - Do you have a boost referenced regulator?

Unfortunately not. This is a completely stock returnless '04 vette fuel system with the addition of injectors, an MSD fuel pump booster, and methanol injection.

Thanks, Ken

[Tordne]

Finally got around to installing this all this today. I spent ages getting it all just so (nice and tidy). Best of all it works :)

Great tutorial TAQuickness!! Wired into EGR of PCM. Pretty easy with the right tools :cheers:

Wile I was doing PCM wiring I also put in the Valet Mode switch ;)

[ringram]

Cool.

[TAQuickness]

awesome. Now send me some logs of your FP and WOT!

[Tordne]

First quick drive around the block I got a min of 15 kPa vacuume and the FP dropped from a pretty constant ~58-60 PSI to about ~53 PSI. Interestingly at ~80 kPa vacuume I was more like 62 PSI

More logging today, and testing the Valet Mode switch ;)

[TAQuickness]

send me any WOT logs you have.

Sounds like you are seeing a similar drop in FP.

[redhardsupra]

i'm curious too to see your FP logs. i've been doing a lot of research on it, and what amazed me is not just the MAP related drop, but also the RPM related drop in FP. even at steady MAP, as RPM go up, the FP goes down, and it does it quite a bit. That's scary to me, because we dont have a table in which we could 'explain' it to the computer to account for it (other than expressing it with VE which I'd rather avoid if i can)
what kind of changes are you seeing, along both MAP and RPM axis?

[Tordne]

I'll get a decent log tomorrow and report the results, probably with some screen shots.

I can see already that if the FP is ~62 PSI at 80 kPa vacuum then this will help my super richness off the gas I've been fighting for ever!!

[y2kws6]

I just set this pid up and got it working. My only problem is that the the pid voltage is moving around to the point I have about a 5 psi in either direction variation at idle and throughout the the RPM range. When I check with a multimeter the voltage is rock solid at 2.79 volts at an idle and I am checking at the ext connector so I know the signal is right. Why would the voltage going in be steady but the read voltage have so much variation. Also the autometer guage is rock solid at 58 psi. I saw there was a post earlier in this thread where a gentleman was having a similar problem but there was no mention of a resolution.

Thanks

Tom

[Tordne]

Did you wire to PCM EGR circuit of FlashScan? Could it be that the reference voltage is not stable?

[y2kws6]

I wired from the return of the sender directly to the ext.ad2 side of the flashscan. The autometer guage is accurate and steady and when I measure right at the ext.ad2 connector i have 2.79 volts steady with no fluctuation(which is the same as the guage). There was a guy that had a similar problem in another thread. His fuel pressure plot is doing the same thing that mine is. Here is what it looks like. http://forum.efilive.com/attachment.php?attachmentid=843&d=1155572671

I have double checked my fuel pressure and it is steady and the funny part is the autometer guage is 100% accurate (when referenced to a mechanical guage on the rail) and the signal to the guage and to the flash scan are identical. I really appreciate your help. This is driving me crazy. :)

[Tordne]

OK...

V1 or V2 FlashScan?

So you have the Orange connector that goes into the EXT.AD2 input, and I read that if that is connected to FlashScan and you measure the voltage from the poles on top of the orange connector you have a stable voltage. But, when watching the logged voltage within the Scan Tool that it is fluctuating. Is that correct?

[y2kws6]

OK...

V1 or V2 FlashScan?

So you have the Orange connector that goes into the EXT.AD2 input, and I read that if that is connected to FlashScan and you measure the voltage from the poles on top of the orange connector you have a stable voltage. But, when watching the logged voltage within the Scan Tool that it is fluctuating. Is that correct?

I am using version 1. You are correct about the logged voltage. Thanks for the quick response.

Tom

[y2kws6]

BTW I tried to switch it to ext.ad1 and it still did the same thing.

[Tordne]

That is very interesting!! Don't suppose you are able to take a video (with cell phone) of the recorded voltage with a multimeter and send to me, along with the log that is taken at the same time? If so send to efilive at holdencrazy dot com

Cheers,

[y2kws6]

That is very interesting!! Don't suppose you are able to take a video (with cell phone) of the recorded voltage with a multimeter and send to me, along with the log that is taken at the same time? If so send to efilive at holdencrazy dot com

Cheers,

I'll do it tommorow. Thanks

[DrX]

Same issue here. No change from V1 to V2. I just pulled the FP input connector out of the V2 and put the meter on it. While idling the voltage was steady at 2.50V with an occasional swing of .01V either way. In comparison, the logged input under the same conditions varied by .6V(max logged value-min logged value). My Autometer gauge did not budge from 51 psi during this period.

Edit: Same thing if I probed the FP inputs while it was plugged into the V2 and logging. Even though the logged value was jumping around, the meter showed a steady 2.50V.

[Tordne]

I'd like to rule out the FlashScan interface, purely for the fact that we all use the EXT.AD inputs for our WBO2's and I have never had reason to question the accuracy measured through the FlashScan interface.

I am obsessive about accuracy etc. and made my own device for calibrating the inputs on the FlashScan V2 interface. When doing this I went to the extent of having one connector off my device connected to both the V1 and V2 interfaces concurrently as well as measuring with a DMM to ensure that all devices were the same :)

The similarity seems to be that your are both terminating the ground and signal at FlashScan. Where is the +5v reference coming from?

I wired mine into the EGR connection on the PCM and from what I've observed it is pretty solid.

[DrX]

I'd like to rule out the FlashScan interface, purely for the fact that we all use the EXT.AD inputs for our WBO2's and I have never had reason to question the accuracy measured through the FlashScan interface.

I am obsessive about accuracy etc. and made my own device for calibrating the inputs on the FlashScan V2 interface. When doing this I went to the extent of having one connector off my device connected to both the V1 and V2 interfaces concurrently as well as measuring with a DMM to ensure that all devices were the same :)

The similarity seems to be that your are both terminating the ground and signal at FlashScan. Where is the +5v reference coming from?

I wired mine into the EGR connection on the PCM and from what I've observed it is pretty solid.

I saw the same thing with both my V1 and V2. When I put the meter on the wideband input it looks pretty close to what is being logged. Although the wideband signal jumps around more on both the meter and log as expected.

My +5V ref to the sensor is supplied by the Autometer gauge via the supplied harness.

[Tordne]

The harness I got had 5 wires, 2 of which were discarded when the square connector end was cut off. Is your's a different harness, cause mine had nothing special for providing the +5v?

[DrX]

The harness I got had 5 wires, 2 of which were discarded when the square connector end was cut off. Is your's a different harness, cause mine had nothing special for providing the +5v?

This is what I have:

http://i114.photobucket.com/albums/n241/TDOC2004/FPGauge.jpg

White wire is for the light. Actually my white wire comes directly from the bulb along with its own ground wire. There is no white wire in the square connector.

[Tordne]

OK.. I'm afraid I'm a little confused (easily done) :confused: ... So are you running 2 sender units (one to this gauge and one to FlashScan)? If so, is the sender unit and harness that goes to FlashScan the parts that are identified in this thread by TAQuickness and Beer99C5?

[DrX]

OK.. I'm afraid I'm a little confused (easily done) :confused: ... So are you running 2 sender units (one to this gauge and one to FlashScan)? If so, is the sender unit and harness that goes to FlashScan the parts that are identified in this thread by TAQuickness and Beer99C5?

One sender to both. Same sending unit you guys are using(0-100psi)as far as I know. 0-5V output. It came with my gauge. Pins can be added to the square connector at #4(-) and #10(+) to connect to their datalogger. I have tried connecting both to pin #10 and just splicing into the signal wire between the sensor and the gauge with the same result.

[Tordne]

Well I'm buggered if I know then. Will have to wait for the smart people to wake up I guess :). I hate not being able to resolve these types of things :mad:.

[Beer99C5]

Grey wire to the sending unit should be 5V.

I believe the gauge steps the 12v to the guage down to 5v to the sending unit. Gauge has the 12V coming in. The sending unit plugs into the gauge, and that is where I think the voltage is stepped down.

Black Ground

Purple output from sending unit...tap into that and send that to the logger.

Thats my guess.

[y2kws6]

Black Ground

Purple output from sending unit...tap into that and send that to the logger.

Thats my guess.

Thats how I have mine setup.

[y2kws6]

Well I'm buggered if I know then. Will have to wait for the smart people to wake up I guess :). I hate not being able to resolve these types of things :mad:.

I'll have a video of the comparison between the voltage thru efilive and on a DMM by tommorow morning for you.

Thanks again for all your help

Tom

[redhardsupra]

here's my newest 2 cents on the topic of fuel pressure:
http://redhardsupra.blogspot.com/2006/12/under-fuel-pressure.html

i hope you guys discover that the fuel pressure senders are good, or otherwise all my work is garbage...

[Tordne]

Good stuff Marcin!

I did a decent log the other day after installing the Fuel Pressure Sender. As a result I changed the spreadsheet that you did (and Andy modified) to calculate each cell for kPa vacuum against the actual fuel pressure for that cell.

It changed the slop of the IFR table quite significantly. I still made it linear but it is a steeper slope than is was simply calculated with the injector rated, actual pressure etc.

[TAQuickness]

Good stuff Marcin!

+1

I don't care what anyone says, you're a fart smucker!

[y2kws6]

That is very interesting!! Don't suppose you are able to take a video (with cell phone) of the recorded voltage with a multimeter and send to me, along with the log that is taken at the same time? If so send to efilive at holdencrazy dot com

Cheers,

I'm going to shoot that video over to you. Let me know what you think.

[Tordne]

Like you say the voltage is very steady and you are measuring with a good meter :) Pretty solid on 2.8xx volts, yet there is a variance of .2 volts through the logged data.

The video look like a GTO or a Commodore - not a WS6 :D

I might go and try this now and see what results I get. If the V1 will run only off USB power I'll try that as well, otherwise it will just be V2 (my install doesn't allow me to change OBDII cables easily :))

[redhardsupra]

so would that be due to a bad reference voltage? if we cannot log reliably with the unit from cyg lighter, then what's the option? bring some batteries? :)

[Tordne]

Blonde moment :Eyecrazy:. I wired my FP unit into EGR so FlashScan doesn't get the voltage input. The measured voltage off the EGR circuit is very stable (like what you saw on the meter).

I testes my WBO2 with engine off and the input voltage was solid for that, and therefore so was the calculated AFR (20:1).

Do you know what the update frequency of the Fluke meter is? FlashScan is logging at 10fps so I wonder if it is getting better (more accurate) resolution. Can you try and see what the voltage in FlashScan is with engine off (ignition on)?

[Blacky]

Do you know what the update frequency of the Fluke meter is? FlashScan is logging at 10fps so I wonder if it is getting better (more accurate) resolution. Can you try and see what the voltage in FlashScan is with engine off (ignition on)?
If you select only external PIDs, FlashScan should log at up to 30-40 fps. If you select 1 vehicle PID (and the externals) then you will probably still get 30-40 fps. Select 1-6 channels (and the externals) and you might get around 20 fps, any more channels than that, and it will start to drop down to the standard 10fps.

Regards
Paul

[y2kws6]

Like you say the voltage is very steady and you are measuring with a good meter :) Pretty solid on 2.8xx volts, yet there is a variance of .2 volts through the logged data.

The video look like a GTO or a Commodore - not a WS6 :D

I might go and try this now and see what results I get. If the V1 will run only off USB power I'll try that as well, otherwise it will just be V2 (my install doesn't allow me to change OBDII cables easily :))

Yeah its a GTO.:D I'll try to find out what the sample rate is of the Fluke 179. I wonder why others that have done this arent having a problem? I know the sender is the standard 0-100 psi sender that autometer uses. I guess I'm just lucky. :)

[y2kws6]

If you select only external PIDs, FlashScan should log at up to 30-40 fps. If you select 1 vehicle PID (and the externals) then you will probably still get 30-40 fps. Select 1-6 channels (and the externals) and you might get around 20 fps, any more channels than that, and it will start to drop down to the standard 10fps.

Regards
Paul


I dont remember how many PIDs I have selected to be monitored but I believe its over 10 and then the two externals.(Although I disconnected the wideband just make sure there was no interference) I'm curious if I were to select more PIDs if it would calm down? Would I be correct in assuming that I would lose the resolution for all the other pids in an effort to get this one to work if I just selected more?

BTW,

I'd like to thank all of you guys for helping me out. The ability to talk to the people that know the most about this stuff is great and I really appreciate it.

[Tordne]

Up to 24 Channels (not PIDs - some PIDs require 2 or 0 Channels so they don't relate necessarily) will log at up to 10fps, above that drops to 5fps. I generally always stay below 24 channels so can't tell you if frame rate drops further.

Happy to help, but don't feel I've been able to yet :sad:.

[sweetdiesel]

this is awsome what you guys are doing!
im wondering if any of you know if i could do this same thing only with a 0-300psi gauge

i notice that Autometer dosnt do this or could you change it so low voltage =0 high voltage = 300psi on there program or EFI in the pids?

[sweetdiesel]

i was just thinking i would be able to take input and x by 3 in my PID correct?

[Tordne]

If the sender you have is 0-5 volts you'll be able to create a PID that calculates the corresponding PSI as well.

[vatman02]

can someone help me out with the install of the auto meter pressure sender install i have an 02 ws6 and cant find the unused egr wires thank you

[TAQuickness]

you will need to install the wires on the PCM harnes. 01 & 02's didn't come with factory EGR, hence, no wires. Beer99C5 just did this to his vette. I think he even updated the thread with the vendors you'll need to contact for the parts. IIRC it cost about $5

[Beer99C5]

http://forum.efilive.com/showthread.php?t=2386&page=3

I think its over at that thread (different Pin for the COS5), but good pictures for putting in the pins.

[TAQuickness]

BTW - Welcome to the forum vatman02

[Ira]

Hi

Hopefully in my quick read of this topic I didn't miss something that will make me appear the fool!

Using an analog gauge or voltmeter to try and guess about the steadiness of a signal is not generally useful and will likely lead you to wrong assumptions. Test the reading with the meter set to a 2V AC scale and see if you don't see a few tenths of a volt. A decent meter on AC will show the noise on top of the DC reading and ignore the DC portion of the signal. If you really want to know, get an oscilloscope and then you'll actually know what's going on. If anyone having this problem is near Los Angeles and wan't to drop over, I'll be happy to tell you what the fuel pressure sendor is actually putting out. It's very likely that the pressure varies by a few PSI or more every time an injector opens and that the spikes are short enough that both the analog gauge and the voltmeter ignore them. The A-D inputs on the Flashscan are fast enough to see those spikes and so you might be seeing a lot of noise through the Flashscan inputs that is filtered out on the meter and gauge.

If you want, it's possible to build a filter between the sender and the FS A-D input that will show you the average reading over the last tenth of a second or so and that might be more what you actually want. Try making a custom PID using damp(EXT.AD,100) and see what happens.

Ira

[redhardsupra]

btw, I kinda realized that looking just at the FP gauge is only a part of the story. injectors work of total pressure, which consists of both dynamic and static. FP gauge measures only static. the dynamic one is based on speed of fluid, which in our case translates to a Pdyn~RPM^2. so basically until we can calculate the Pdyn, you should have a quadradic dropoff in FP as RPMs climb. if it drops off more than that, then you have a bottleneck somewhere.

[vatman02]

you will need to install the wires on the PCM harnes. 01 & 02's didn't come with factory EGR, hence, no wires. Beer99C5 just did this to his vette. I think he even updated the thread with the vendors you'll need to contact for the parts. IIRC it cost about $5

i thought it was odd to have wires that had no connection i just didnt understand the pin out part got it now thanks for the help TA and the link from BEER99C5 was spot on for the pics thanx for the help BEER99C5 went back 1 page and found the link for the parts now i just need to wait for ups thanx again for the help ps. ive been lurking around here for a year im just to hard headed :bash: to ask for help

[DrX]

Hi

Hopefully in my quick read of this topic I didn't miss something that will make me appear the fool!

Using an analog gauge or voltmeter to try and guess about the steadiness of a signal is not generally useful and will likely lead you to wrong assumptions. Test the reading with the meter set to a 2V AC scale and see if you don't see a few tenths of a volt. A decent meter on AC will show the noise on top of the DC reading and ignore the DC portion of the signal. If you really want to know, get an oscilloscope and then you'll actually know what's going on. If anyone having this problem is near Los Angeles and wan't to drop over, I'll be happy to tell you what the fuel pressure sendor is actually putting out. It's very likely that the pressure varies by a few PSI or more every time an injector opens and that the spikes are short enough that both the analog gauge and the voltmeter ignore them. The A-D inputs on the Flashscan are fast enough to see those spikes and so you might be seeing a lot of noise through the Flashscan inputs that is filtered out on the meter and gauge.

If you want, it's possible to build a filter between the sender and the FS A-D input that will show you the average reading over the last tenth of a second or so and that might be more what you actually want. Try making a custom PID using damp(EXT.AD,100) and see what happens.

Ira

Makes sense. Haven't had a chance to play with this for a while. Will give it a try when I get a chance.

[Chuck L.]

may do the job.
Measurement Specialties has 1, part No: MSP-600-100.
It's available from Digikey. Price I just found was $95.00USD.
Saw this info on another board, [Gary Z, Ls1tech posted it]. I am going to try to make 1 work...

[Ira]

The hot ticket is to watch ebay. I bought a few MIL spec versions of that for $10 or $15 each or so a few years back.

Ira

[mr.prick]

[QUOTE=Beer99C5]Waiting on the harness...

http://www.retrorelics.net/jim/Boards/Corvette/FuelpresSunit.JPG

could you tell me the wire pin outs for this connector.
i am making my own harness for this sensor.
thanks

[Beer99C5]

Looking at it as pictured


Black is Left, Grey is Right
_____Purple Single______

From what I can tell from one of my Pics
(out of country, so not car is not available to me)

http://www.retrorelics.net/jim/Boards/Corvette/Nov06a.JPG

[mr.prick]

Looking at it as pictured


Black is Left, Grey is Right
_____Purple Single______

From what I can tell from one of my Pics
(out of country, so not car is not available to me)

http://www.retrorelics.net/jim/Boards/Corvette/Nov06a.JPG
with the clip facing up?
are there numbers on the connector?
i don`t want to screw the sender up it was $90

[Beer99C5]

To be sure go to the autometer site and submit the question on their form, they are good about getting back to ya, usually within a day.

[Mr. P.]

OK I got a question - would it be possible to use a 0-80 lb oil pressure sending unit? Hook it up to one of the 12V inputs on the V2??? I can't see why not, I mean they both measure pressure of a petroleum product so I would think safety wouldn't be an issue... If so it sure would be nice to get a $10 sending unit to do the same job. Feedback anyone?

Mr. P.

[Beer99C5]

OK I got a question - would it be possible to use a 0-80 lb oil pressure sending unit? Hook it up to one of the 12V inputs on the V2??? I can't see why not, I mean they both measure pressure of a petroleum product so I would think safety wouldn't be an issue... If so it sure would be nice to get a $10 sending unit to do the same job. Feedback anyone?

Mr. P.


The data needs to be 0-5V, that is what is used to get the pressure. The 12 Volt inputs are used for relay's indication and have a value of 0 and 1, 0 if there is no power to the relay, and 1 if the relay has power.

[TAQuickness]

The data needs to be 0-5V, that is what is used to get the pressure. The 12 Volt inputs are used for relay's indication and have a value of 0 and 1, 0 if there is no power to the relay, and 1 if the relay has power.

+1 ;)

[Mr. P.]

The data needs to be 0-5V, that is what is used to get the pressure. The 12 Volt inputs are used for relay's indication and have a value of 0 and 1, 0 if there is no power to the relay, and 1 if the relay has power.
Thank you, did not realize they were switched inputs.

Mr. P.

[mr.prick]

"A" is black (ground)
"B" is gray (5v reference from the gauge to sender)
"C" is purple (return signal from sender to gauge)

3433

[mr.prick]

*UNITS

#Code System Abbr Description
#-------- ---------- -------- -------------------------------------------------------------

PSI Imperial PSI "Pounds Per Square Inch"
# ================================================== ============================
# Add slot definitions here
# --------------------------------
# See sae_generic.txt for more information on "SLOT" formats
#
#Units Low High Fmt Expression
#------------ ------------- ------------- ---- --------------------------------------------------------------
*CLC-00-001
PSI 0.00 100.00 .2 "({EXT.AD1}*25)-12.5"

# ================================================== ============================
*PRN - Parameter Reference Numbers
# --------------------------------
# See sae_generic.txt for more information on the *PRN section
#
#Code PRN SLOT Units System Description
#------------------------- ---- ------------ ---------------- ---------------- ------------------------------------------
CALC.FP F001 CLC-00-001 PSI Fuel "Fuel Pressure"


if 0v=0psi and 5v=100psi
should`nt it be {EXT.AD1}*20)?
i ask because with no voltage it shows -12.5psi.

[mr.prick]

*UNITS

#Code System Abbr Description
#-------- ---------- -------- -------------------------------------------------------------

PSI Imperial PSI "Pounds Per Square Inch"
# ================================================== ============================
# Add slot definitions here
# --------------------------------
# See sae_generic.txt for more information on "SLOT" formats
#
#Units Low High Fmt Expression
#------------ ------------- ------------- ---- --------------------------------------------------------------
*CLC-00-001
PSI 0.00 100.00 .2 "({EXT.AD1}*25)-12.5"

# ================================================== ============================
*PRN - Parameter Reference Numbers
# --------------------------------
# See sae_generic.txt for more information on the *PRN section
#
#Code PRN SLOT Units System Description
#------------------------- ---- ------------ ---------------- ---------------- ------------------------------------------
CALC.FP F001 CLC-00-001 PSI Fuel "Fuel Pressure"


if 0v=0psi and 5v=100psi
should`nt it be {EXT.AD1}*20)?
i ask because with no voltage it shows -12.5psi.
:nixweiss:
am i wrong?

[joecar]

I thought 0.5V=0psi and 4.5V=100psi.

[sweetdiesel]

well I'll be a post whore...

In this post you attached a Schematic of the EGR
Any chance you know where i could get one for a 05 LLY Duramax diesel?
I found one for the ECM but its not showing the wire colors and I also have a fluke but i dont seem to be getting any 5 volt power from and of my EGR wires

I have un plugged the EGR plug from the motor and Im checking each pin with no luck?

Any help would be apreciated

Thanks Simon

[TAQuickness]

This is what my manual has for an '05 LLY EGR pin out. Click the pic for a larger, readable, version.

http://98.200.107.1/efilive/forum/s05_lly_egr.gif (http://98.200.107.1/efilive/forum/05_lly_egr.gif)

[sweetdiesel]

TA you are the best, Thanks so much!