Rich or Lean No In Between

[claya2]

I recently finished building a iron ls1 for my truck. It has 42# Delphi Injectors, Comp Cam 219/227, 11:1 Compression, DCR is around 8.75:1. After start up it ran okay and once I began tuning it ran great till about 4000rpm. Which is as far as I got in rpms before it started acting up. Now after about 200 miles it is either really rich or really lean from idle till 4000rpm. No matter where I set the VE add 1 or subtract 1 and it goes the other direction (Rich or Lean). Both my wideband and my O2's agree on this (7.4 or 20.1). When I turn on fuel trims it switches really fast between the two. It just can't find a middle ground to run. I am stumped because it ran great for 200mi then this. Please, help it is my DD. Have had to drive my mud truck lately and no a/c is not my favorite in Texas heat. Thank You, in advance.

[blownbluez06]

Try failing your MAF, dialing in the VE table and see if it settles down. If it does, might be a defective MAF or one that needs cleaning. CRC makes MAF cleaner. Oil from K&N and other filters can mess them up.

[claya2]

maf is disabled and truck is in SD mode already. I did not finish tuning in SD before this happened.

[blownbluez06]

Any chance you still have the MAF in the table or chart? If so, you need to remove it. Having it in the scanner will bring it back into the fuel calculations (at least sometimes it has screwed me up).

[claya2]

It is still in the list. However, this problem is current even without the scanner hooked up.

[blownbluez06]

You're not talking about the 02's switching in closed loop are you? They're supposed to switch between rich and lean in closed loop. That's natural. My wideband doesn't bounce around as much as the narrowbands do.

[Google]

maf is disabled and truck is in SD mode already. I did not finish tuning in SD before this happened.

Maf is not failed correct, incorrect injector data, this is more then likely your issue.


http://www.hptuners.com/forum/showpo...35&postcount=2


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[claya2]

Thanks, Google. I will try that today on my lunch break. I am just confused how it ran good for 200mi. This is definitely not closed loop operation.

[claya2]

Okay, I have failed the MAF properly. It is showing P0103 faster than before so I know it is disabled. Previously I was setting Engine Diagnostics/Airflow/MAF Fail High to 0. Still have same problems after changing to your way. Google you mentioned that the injector data was not correct. I used the injector data from another tune using the same injectors. They flow more than they are rated at due to the increased fuel pressure on the ls1 style motors. 58psi vs. 45psi

Please Help Me!
I am willing to Pay-Pal money to get this corrected!
Here is a SD log with fuel trims enabled. I did this using the stock tune with new inj. data, fuel x1.15, and failed MAF. I tested this before logging if you wonder why it starts with trims already. Previous SD tune that truck was running on just shows way lean or rich (depending on rpm).

[claya2]

Upgraded to enhaced 1 BAR MAF to see if it might be an OS problem. NO LUCK. However, real time tuning is nice still doesn't help me. Current tune file that I have.

[Google]

You need to clear LTFT's seeing how you have them dissabled in the tune you posted #10. Yet the log#09 Shows they are not 0.



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[OldSkool69]

Try Flow rate 41.1 in all the line.

Also try to match you tables for Advance like 23 degrees in all (Ho, Lo, Drive, park)

Are you keeping the Maf, or just gonna stay SD?

[Google]

Try Flow rate 41.1 in all the line.

Also try to match you tables for Advance like 23 degrees in all (Ho, Lo, Drive, park)

Are you keeping the Maf, or just gonna stay SD?

Flow rate will not cause his problem, and trying or guessing injector data is not a solution that should be tryed even when you know the type of injector used.




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[claya2]

You need to clear LTFT's seeing how you have them dissabled in the tune you posted #10. Yet the log#09 Shows they are not 0.



.

The tune in #10 is the sd tune I am working with. If i set the VE say at 49 in cell 55kpa x 800 rpm it is all the way lean. Change that cell value to 50 and it goes all the way rich. The reason for the log in #9 was to show how the o2's swing so far with trims enabled. My wideband goes from 7.4 to 20.1 these are the limits that it will read.

[claya2]

Try Flow rate 41.1 in all the line.

Also try to match you tables for Advance like 23 degrees in all (Ho, Lo, Drive, park)

Are you keeping the Maf, or just gonna stay SD?

Plan on keeping the Maf just been trying to dial in VE tables before enabling the Maf. I will match the advace in all but don't understand how that will affect fueling.

[OldSkool69]

41.1 was what I had with 58psi FP and 42 injectors and maf tune.

Worked for me.

Just my tip

[Google]

The tune in #10 is the sd tune I am working with. If i set the VE say at 49 in cell 55kpa x 800 rpm it is all the way lean. Change that cell value to 50 and it goes all the way rich. The reason for the log in #9 was to show how the o2's swing so far with trims enabled. My wideband goes from 7.4 to 20.1 these are the limits that it will read.

understand..


PM
Sent

[claya2]

The big question for me is why did it run great for 200mi. While I was tuning then I parked it for six hours. Got back in it and everything was crap.

[Google]

post your stock file.




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[claya2]

Here is stock tune.