Injector Duty Cycles 298%!!!!!!!!!

[CTP Racing]

I have a 98 camaro that is procharged with the p-1sc. They shipped this kit with 42 lb/hr injectors and I believe I rescaled them right for EFI Live. The only trouble now is my injectors say 298% duty cycle when I rev it up in nuetral. I am tried everything and nothing seems to remedy the problem any closer to the 80% mark. At idle with no throttle it reads about 55% but as soon as throttle is applied it jumps to over 100%. I am kinda new at this but any help would be greatly appreciated and I would be more than happy to post or send any need log files or info. Also I forgot to mention that I did install a 2 bar map and did the appropriate rescaling of the kPa maps as well.

[foff667]

might wanna post your .tun file...something isnt right if your at 55% at idle

[ringram]

Yeah or list out your IFR settings for us to check

[TAQuickness]

You may want to send a PM directly to RedHardSupra.

[joecar]

Does the bottom of the scan tool window show the correct vin/os/trans...?

[redhardsupra]

send logs and bins

[CTP Racing]

I was out for the weekend and sick for the first part of the week. The os looks correct as fae as I can tell. The car is a 98 and the vin looks correct for a 98 with a manual trans. We have put a turbo 400 trans in it and that seems to be the only thing I have changed that seems to be working correctly. I didn't even bother making a log because I shut the car down long before we got any time into the run. One other thing to add is the procharger kit shipped with 38lb/hr injectors so they are not 42 lb/hr like I wrote before

[CTP Racing]

Here is the tuning file and the log file. I can't give the car any throttle whatsoever without getting over 100% duty cycle. Just so you guys know here is what I have done so far:

1) Made changes for changing manual to auto trans - all that seems to be working great

2) Rescaled the injectors using the excel spreadsheet from the net for 38 lb/hr injectors

3) Vehicle has a 2 bar map installed - I copy and pasted columns in the VE table to cut the resolution in half (ex. what was in the 80kpa column got copied to the 40kpa column and then I made the columns from 55 -105kpa as best I could.

[dc_justin]

Here is the tuning file and the log file. I can't give the car any throttle whatsoever without getting over 100% duty cycle. Just so you guys know here is what I have done so far:

1) Made changes for changing manual to auto trans - all that seems to be working great

2) Rescaled the injectors using the excel spreadsheet from the net for 38 lb/hr injectors

3) Vehicle has a 2 bar map installed - I copy and pasted columns in the VE table to cut the resolution in half (ex. what was in the 80kpa column got copied to the 40kpa column and then I made the columns from 55 -105kpa as best I could.

Oooh, quick question for you. When you did the 2-bar re-scale, did you do it using VE % units, or one of the other units available? (g/cyl, default units, etc).

If you did this using the % method, then your VE table is going to be considerably far off, which it appears is the case... if you look in the information window at the VE equation, it takes kPa as a variable in determining the VE unit. (I did mine this way initially, then saw that MAJOR correction was needed with the wideband hooked up, then noticed the equation issue and changed to g/cyl and all was well).

Also, for 38lb injectors, your IFRs are a bit high. Viewing the IFR table in #/hr, ranges from 44.6#/hr to 48.7#/hr, seems like 38#s should be around the midpoint (since you're re-scaled) of that table.

Not sure redhardsupra's spreadsheet will work properly considering that you're using a 2 bar map and the PCM doesn't realize it...

[CTP Racing]

I emailed Paul and this is what he replied:

I am sorry but I do not know the exact details of tuning the 98 LS1 with a 2bar.

For boost of less than 8psi you can usually get away with leaving the MAF in place and the MAF
will read the extra airflow up to about 8psi.

For boost over 8psi, the forced induction guys have done it for years by removing the MAF sensor
and running in SD mode, then rescaling the MAP sensor calibrations {C6301} and sometimes {C6302}
so that at key on, engine off the MAP value read by EFILive's Scan Tool is exactly half
barometric pressure.

i.e. you start with a 1 bar sensor and check the MAP value at key on, engine off, say it was
98kPa (14.2psi). Then install the 2 bar sensor and adjust {C6301} so that the MAP sensor reads
half of 98kPa, i.e. 46kPa (6.67psi).

Then on the tables that use MAP as a column or row lookup value you need to re-tune the table
values so that the MAP values in the column/row labels actually refer to double what they are.
i.e. In the VE table, the column headed by MAP value 60 kPa (8.7psi) now refers to a real MAP
value of twice that, 120kPa (17.4psi).

Then just to clarify I emailes back and he sent this:

Pretty much all tables that use MAP as one of the axis need to be adjusted. The 1bar MAP sensor sends 0-5V to represent 0-100kPa to the PCM (actually its 10-110, but I'll use 0-100 to make this explanation a little easier to undertand). So basically, when the PCM sees a voltage of 2.5V it assumes the MAP pressure is 50kPa. When you change the MAP sensor to 2bar and rescale the settings I explained previously, the 2bar MAP sensor sends 0-5V to represent 0-200kPa. So at 100kPa the 2 bar will only send 2.5V. The PCM will "think" it is seeing 50kPa from its stock MAP sensor.

So in all your MAP tables you need to take the values in the table from the 100kPa column and put them in the 50kPa column, and all the 90kPa values into the 45kPa column and the 80kPa into the 40kPa column etc. The values in the "inbetween" columns can be discarded. If you really want to get picky, you could average the three values (i.e. the column you are copying and the two columns either side).

The values in the 55..100kPa columns will represent the boost columns from 100-200kPa. You will need to fill those with values that correspond to boost conditions.

You can easily copy and paste entire columns at a time by right-clicking on the column heading and selecting Copy. Then right click on another column heading and select Paste->Paste

Once you have made all those changes, when looking at the tables with MAP as a row or column value, you will need to mentally assume that the MAP value is actually double what you are looking at. i.e. column 50kPa is actually 100kPa.

Note: the Scan Tool will always report the MAP at half of the real value - i.e. at keyon engine off, it should be showing 50kPa (assuming barometric pressure is 100kPa).

So basically everything that referenced kpa value was actualing seeing half. So what was in the MAP kpa column for 100kpa I put all those numbers and copied them into the 50kpa column, 80 went into the 40 column etc... Basically as it was explained to me was that with the key on but the car not running the 2 bar sensor would read half of what the 1 bar did. So everything is basically the same except after 50kpa the sensor is actually reading boost pressure so I was on my own for fudging the values in that part of the table. Is that correct or is there a btter way. I just have not found a lot of info and Paul was the best help so far.

[dc_justin]

That is exactly what needs to be done, but you cannot do it using the EFILive theoretical maximum VE % units. Go to the Edit menu, then Properties. Change the first option there, Volumetric Efficiency Values, to read in g/cyl instead of VE.

When I do that and compare your VE table to the VE table of a stock one, the difference is extremely minor. Less than 10% gain at the 105kPa level.

I am slow and haven't upgraded to a custom OS yet, but am still using a 2-bar map, much the way that you are. To get it right, my VE % value was upwards of 300% by 80kPa to provide the proper fueling...

So, to do what you need to do, convert the units to g/cyl, then copy the 30 column to the 15, 40 to 20, 50 to 25, etc to 100kPa column. Then, take the 105kPa column and multiple it by 200% or so. Highlight 50kPa to 105kPa, all rows and press the button that is a light blue left right arrow, like this <-->.

Do the same with your backup VE table and VE while cranking.

[dc_justin]

I've gone ahead and made these changes for you, along with a few to the Barometer settings, as you do not want it to update on you. I have also halved the MAP offset value in the C6302 param.

I have also made some changes to the IFR table, as your 38# injectors should flow 38#s at atmosphere, which with your 2Bar, will be a vaccum reading of approx 14.9 Greater vaccum will cause injectors to flow more, boost will cause them to flow less.

Thank God for my vac referenced FPR, as I'm glad I have one number for all values of this table. :rockon:

Edit: I used VE tables in the tune you attached, rather than grabbing them from another tune, as they are very close to stock values. My 2002 WS6 has a higher g/cyl value at 105kPa than your VE table was showing...

What you absolutely must do to get your tune right is hook up a wideband now and perform the autotune procedure. It is very easy to do and can have your VE table nailed down in a couple of hours (if that).

[CTP Racing]

Thanks for the help, I am on that right now. The only question I have left is on the Auto VE tuning. All the instructions are for 99-00 or for 2001+ so I am not totally sure what I need to do for the 98. Do I just follow the instructions for the 99??? Thanks again

One other thing. I tried to download the .tun file you posted but when I save it to my computer it says it is "attachment.php" so it doesn't even recognize it as a valid efi file. If you need to email it to me the address is carandtruckpros@yahoo.com

[dc_justin]

Thanks for the help, I am on that right now. The only question I have left is on the Auto VE tuning. All the instructions are for 99-00 or for 2001+ so I am not totally sure what I need to do for the 98. Do I just follow the instructions for the 99??? Thanks again

One other thing. I tried to download the .tun file you posted but when I save it to my computer it says it is "attachment.php" so it doesn't even recognise it as a valid efi file

Follow the same instructions. Make 2 BEN maps though, one with kPa columns of (15,20,25,30,etc) for the Primary, and one for the backup VE table (10,20,30,40,etc). These tables should be consistent with each other, as in SD mode, the backup VE table is used instead of the primary. Which means that the tune file I created is probably slightly off. Let me adjust it and re-attach.

To download, when you are saving, change the file type in the save box pull down to "all files" and rename it from "attachment.php" to "camaro_000.tun"

Look for a new file soon.

[CTP Racing]

I reflashed the tune you sent and the car sounds good at idle and revs up much easier than before. The map reads 46kpa at key on but not started so that is right where it needs to be. The injector duty cycles got a little bit worse however and are at 60%+ at idle. With just a little rev up they get right around the 300% duty cycle mark. I just don't really wanna run it hard trying to tune and damage the injectors. What else is tied into that to make the duty cycles so high. Will that change when I try tuning is SD mode. Also, will the duty cycle change once the vehicle enters open loop because we didn't let it warm up fully with the log I posted.

[dc_justin]

Will you make another log file and remove the following PIDs:

FTC
FUELSYS

And Add in GM.AFR

Do you have a wideband hooked up? If so, please log the appropriate wideband PID as well.

Also, if you have your stock tune as well, could you post it up?

Thanks

[redhardsupra]

I finally looked at the original tune/scan (sorry it took so long, been busy) and it just looks like everything is fine, except the values for pulse width, so obvieously the duty cycle is gonna be screwed as well. I'd check the electrical connections, maybe you're reading the signal off a wrong wire. i'm amazed frankly that this thing runs at all with the numbers being off that much. do you have a wideband? what afr do you get at idle?

[CTP Racing]

Here is the stock .tun file, the same file with strictly trans changes done to make everything work correctly like the speedo. We went from manual to automatic. The AFR at idle is like 1.05 Lambda. Just a tine bit lean but reads fine for idle.