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Cam72aro
March 2nd, 2009, 01:17 PM
I did the auto ve process and did the copy, past , multiply with labels process for my main ve table, then I tool the car out of SD mode and the car ran real lean and would barely run. Can someone look at my log file and tell me what I did wrong? Thanks a mil guys, Josh

hquick
March 2nd, 2009, 07:24 PM
It'd be a good idea to post up your tune as well. Also...details of your vehicle, engine size, mod's etc...

Cam72aro
March 3rd, 2009, 05:36 AM
I dont have acess to the tune right now from this computer, but its a stock ls1 with a t rex and all bolt ons. Its a 6 speed also.

5.7ute
March 3rd, 2009, 02:24 PM
I did the auto ve process and did the copy, past , multiply with labels process for my main ve table, then I tool the car out of SD mode and the car ran real lean and would barely run. Can someone look at my log file and tell me what I did wrong? Thanks a mil guys, Josh

Unless the rest of your tune is precise & your filtering removes all transient data you will not get your VE table in line with only one pass.
Also when you took the car out of SD mode you are running on a hybrid of MAF & SD fuelling.
I would leave the car in SD mode & verify that the AutoVE has worked & your Bens are between 0.98 & 1.02. Even closer to 1.0 if you can.
Set B0120 to 800 & go through the Automaf process.( This gets fuelling calculated by the maf only) Then set B0120 back to stock & verify that your AFR's are in line.

joecar
March 3rd, 2009, 02:36 PM
+1.

Also, what does your IFR look like...?

This is for your 72, right (I'm assuming)...? What was the donor vehicle for the PCM and other parts...?

Cam72aro
March 3rd, 2009, 03:37 PM
+1.

Also, what does your IFR look like...?

This is for your 72, right (I'm assuming)...? What was the donor vehicle for the PCM and other parts...?
I havent touched the Ifr table because I have stock injectors. Yes this is for my 72. The motor and trans is from a 99 T/A. I will post my tune when I get back home on Friday.

5.7ute Leave it in sd and do the auto ve several times? It should get better if I do it several times? Josh

5.7ute
March 3rd, 2009, 04:11 PM
Yes. Especially if done on road. This is due to quite a few reasons but the main ones are:
Interpolation by the pcm with corresponding cells. Due to the limited resolution in the cells, the pcm uses a weighted amount from the surrounding cells. FI if you were doing 2400rpm at 30kpa map, only this cell will be used. But if you were doing 2400rpm at 32kpa map, a weighted amount of the 35kpa cell will be added for the airmass calculation. Unless the 35 kpa cell was correct this will give you bad data & your BEN calculation for the 30kpa cell will be out. Several runs of the process will slowly minimise these errors to the point where they have a negligable effect.
Transient fuelling. This can cause a lean or rich reading on throttle transients & is very hard to filter out since it decays over time. Again this will cause errors in your BEN data.
There are a few threads on here in regards to getting good data that are well worth having a search for. Good luck & keep us posted.
Cheers Mick

joecar
March 3rd, 2009, 04:38 PM
While driving to capture a log for AutoVE (or AutoMAF), see if you can operate the throttle in a smooth sweeping manner...

you can still go to WOT, but instead of instantly snapping the throttle wide open, sweep/ramp it open over some period of time until you get to WOT (and then keep it there... this can be scary... :D )...

of course, watch out for your speed and the road and how much room you have...

I know this may not be easy to do... but it will give you better data, the filter won't have to eliminate as many transient data portions.

Cam72aro
March 7th, 2009, 12:50 PM
Here is my tune file. If someone could look over it and tell me what you think I would appreciate it. Thanks, Josh

5.7ute
March 8th, 2009, 12:16 PM
Josh, what is your reasoning behind the rich commanded fuel table (B3605) & extremely rich PE table (B3618)?

Cam72aro
March 8th, 2009, 02:52 PM
I had a real bad stumble when you would get into the throttle. The only way I could correct it was to richen the b3618 table. I am not sure why the b3605 table is like that. It shouldnt matter after the car goes into closed loop though, right? What should the b3618 table look like?

5.7ute
March 8th, 2009, 03:43 PM
Being N/A I wouldnt think you would need to go any richer than 12.5:1 in your B3618 table. Unless of course you are trying to make up for a fault in your airmass model (VE or maf tables) or transient fuelling tables (not available in your OS at this time)
Do you have a log of the stumble with wideband AFR you can post?
Was the B3605 table like that stock?

SOMhaveit
March 9th, 2009, 02:33 AM
Well, someone has changed the IFR from stock configuration. Your tune is set up for a system with a return fuel line and a fuel pressure regulator tied to manifold vacuum. The 99 TA didn't have that.

So what is your fuel set up and what is your fuel line pressure and is it in fact referenced to intake vacuum?

As far as running closed loop, you aren't likely to get a tune you'll be happy with if you're changing the VE table and not looking at modifying the MAF curve and maybe tweaking IFR. That stock MAF curve was arrived at with the oem air intake configuration, cam, and exhaust.

GM dicks with IFR #s, VE #s, and the MAF curve to "get it right."

Anyhow, unless you get the fueling issue battened down, you're going to be chasing your tail with this even more than most of us.

SOMhaveit
March 9th, 2009, 02:40 AM
Oh, and your PE modifier based on RPMs is nutz. Commanding 9.5 AFR ? The oem table commands 11.7 straight through, and that needs to be brought in line with something between 12.5 and 13.2, provided what you command is very near the result.

I'm no expert on this stuff. There are, I believe, some bonafide experts on this forum and HPtuners forum. I just mess with it for my own car, and don't understand all of the interrelationships of the tables, but I know enough to see that your tune is whacked.

joecar
March 9th, 2009, 02:53 AM
Yes, check between the fuel rails for the fuel pressure regulator (not the pulse damper)... your flat IFR is for a referenced FPR (which is located in front, "between" the rails).

If there is a FPR between the rails, it will have a reference hose connecting it to the intake manifold, and a return line... but as SOMhaveit says 1999 F-car had a returnless fuel system, (the return line is at the rear, immediately past the filter, the regulator is in the tank and has no MAP reference)... in this case the IFR is sloped with MANVAC.

Can you post a picture of your engine compartment and of your fuel filter...?

Have you measured rail pressure...?

With MAP-referenced FPR (return system), rail pressure goes up when you open throttle.

With unreferenced FPR (returnless system), rail pressure stays constant as you open throttle (to within 2 psi).

Cam72aro
March 9th, 2009, 03:22 AM
I am running a walbro 255 with a corvette regulator/ filter right by the tank. There is only a feed line to the rail. There isnt a regulator between the rails, just the dampner. Pressure is stock at 58psi. So I should start with the IFR table? Then the PE modifer based on rpm?

SOMhaveit
March 9th, 2009, 03:28 AM
Yes. Go to holden crazy and start with a stock IFR table.

joecar
March 9th, 2009, 11:24 AM
Do that and then sanity check it by calculating using the spreadsheet: http://www.marcintology.com/tuning/injectors.xls

More info:


Injector Flow Rate:
showthread.php?t=4821 (http://forum.efilive.com/showthread.php?t=4821)

Cam72aro
March 9th, 2009, 02:20 PM
B3605 is completely stock. I adjusted the IFR table to what is in the attached file. I also changed the PE modifer B3618 table to 12.5 across the board. Is this a good starting point or am I off for a starting point? Should I do the auto ve now and see what it gives me on the main ve table? Thanks for the help and please let me know what I should to to get this thing running right? Josh

SOMhaveit
March 9th, 2009, 03:19 PM
That's what I would do. Start it up while logging data and watch Actual AFR with your wideband. If you see very lean or rich data, stop and adjust the VE table globally to go where you need to be - higher VE values for richer AFR, lower VE values for leaner AFR.

Just be cautious and don't peg it with a lean AFR.

You're headed in the right direction now.

Cam72aro
March 9th, 2009, 03:22 PM
That's what I would do. Start it up while logging data and watch Actual AFR with your wideband. If you see very lean or rich data, stop and adjust the VE table globally to go where you need to be - higher VE values for richer AFR, lower VE values for leaner AFR.

Just be cautious and don't peg it with a lean AFR.

You're headed in the right direction now.

Thanks for the help. I will work on it some this week. Josh