I have an lm7 I've been tuning. I have the maf and ve tables done but when I re-enable the o2 sensors it will go into open loop at idle and run a little lean. I bumped up the idle a little bit and it helped. But still does it from time to time. I'm thinking the headers could be screwing with the o2s possibly. Any advice would be much appreciated.
What computer and vehicle? Tune file or logs?
Does the commanded AFR change at all when this happens?
2016 Silverado CCSB 5.3/6L80e, not as slow but still heavy.
If you don't post your tune and logs when you have questions you aren't helping yourself.
02 Silverado 411 pcm with the 5.3. Yes commanded does change to a leaner value when it does this. Can't upload a log at the moment I'm on my phone. I'm not sure why it's comanding a leaner value. Also when it does this o2 readings go flat like it's turning them off.
Sounds like a cat test.
Do you have the cat converters still? If you don't did you make sure to disable all the codes and COT?
2016 Silverado CCSB 5.3/6L80e, not as slow but still heavy.
If you don't post your tune and logs when you have questions you aren't helping yourself.
No cats cot is turned off and all rear o2 sensor stuff is disabled. I'm starting to think the o2s either need replaced or the long tube headers are causing the o2s to not stay hot enough. I'm logging the fuel system status when cold started it says closed loop not ready after warm up it goes to closed loop but sitting at a red light it will go open loop/ accel after a few seconds then as soon as I touch the fuel it goes back to closed loop. It doesn't seem to affect driveability or anything other than have a slightly lean idle. Stock idle was set to 550rpm it did it every time I would stop bumped idle to 625 for the hell of it now it randomly does it.
any codes? I went to the Corvette O2s Bosch13111 Long wire but a bigger heater. Seemed to fix my problem with my long tube headers Had codes p1133 andP1153
No codes
I always saw this problem with P59 computers. That solution was to plug the rear o2 sensors back in and just tied them up out of the way.
2016 Silverado CCSB 5.3/6L80e, not as slow but still heavy.
If you don't post your tune and logs when you have questions you aren't helping yourself.
I will give that a shot easy enough to try lol
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