Closed loop makes car go LEAN
04-24-2011, 07:32 PM
#1
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Closed loop makes car go LEAN Ok, so I drove the car around last summer OLSD tune. Would hold 14.7 great but would require tweaking every so often.
Decided to get to turn the 02 sensors back on. So put in brand new Bosch sensors and enabled CL. Do not have the 02 sensors crossed (you can easily do this to the fronts 02 sensors on a Vette)
This is the problem. Once the car warms up it slowly goes lean and I can watch the LTFT spread apart. I can repeat the problem if I clear the fuel trims then hit "fuel trim learn ON" It takes about 3-4 seconds it instantly goes lean and the LTFT spread.
Attached is my log and my tune.
Car runs great in OL, but would like to remove constant tweaking. This is a 2bar SD tune.
80lb injectors
the fuel pressure regulator is boost referenced
had to scale down the injector kPA offset and VE table because i was exceding the max values.
Any input?
Decided to get to turn the 02 sensors back on. So put in brand new Bosch sensors and enabled CL. Do not have the 02 sensors crossed (you can easily do this to the fronts 02 sensors on a Vette)
This is the problem. Once the car warms up it slowly goes lean and I can watch the LTFT spread apart. I can repeat the problem if I clear the fuel trims then hit "fuel trim learn ON" It takes about 3-4 seconds it instantly goes lean and the LTFT spread.
Attached is my log and my tune.
Car runs great in OL, but would like to remove constant tweaking. This is a 2bar SD tune.
80lb injectors
the fuel pressure regulator is boost referenced
had to scale down the injector kPA offset and VE table because i was exceding the max values.
Any input?
04-24-2011, 09:41 PM
#2
Your 02's aren't even switching in that log that I can see. Has me wondering if you have a wiring problem causing the heaters to not work or something. If you have them disabled, I would recommend turning on all of your sensor 1 DTC's to see if the PCM sees what I'm seeing in hopes that it will help you discover the problem.
Last edited by BLOWNBLUEZ06; 04-25-2011 at 12:03 AM.
