New issues after PCM change and full exhaust - One side rich one side lean
Hello tuners, back again..
I now have full exhaust on my van and have a new set of logged issues. I went through the steps on the idle tuning thread (https://forum.hptuners.com/showthrea...hlight=krambo) and set things as the instructions labeled. I was having this misfire issue before I went back and tried these steps, so it's not these changes that started it.
My drivers side is running very rich (.8 to 1.0) while my passenger side sits happily at .1 to .3.
Doing some reading, I found the test for a bad o2 sensor. There was debate about if welding next to an o2 sensor causes issues, so since I just had exhaust done yesterday (and the guy unplugged the o2 sensors before welding) I went out and swapped the sensors to opposite sides, with the same results. Driver side is rich, passenger is fine. They were a little sooty when I pulled them out, but no welding slag on them or massive chunky residue clogging them.
While doing the datalogging, I noticed that on my LTFT bank 2 was a -1.25 but my driver side was +25. That's a pretty huge difference.
My combo is a 2000 5.3, 209/217 @ 112* cam with new springs and stock 4L60E trans. Only other internal upgrade was a dual roller timing set.
Anyone have an idea why it's dumping fuel on one side but not the other?
*EDIT* I'm also not getting any codes for this problem
You said you fixed the misfire issue. Did you reset the LTFT in Special functions afterward? Re- Enable the LTFT then reset them. If that doesn't help it then it could be a leak or wiring. Are you using wiring extensions? Trace the colors/wires and make sure they are not backwards on the one side. The trims are almost perfect opposites after second throttle blip.
I have not reset the LTFT.. I will look into that.
I just pulled the drivers side plugs and they were sooty, but not completely fouled. I cleaned them (They were brand new 3 months ago and literally have maybe 1 mile on them just cruising my court and on and off the trailer) and regapped them from 60 to 55.
I am not using wire extenders. When I reworked the harness to de-pin the stuff I didn't need I was really careful to put the harness back in the right configuration. I think I remember even testing the wires to the PCM to make sure I had the sides on correctly. I will attempt to reset the LTFT and upload the results...
Ok did some testing. Went out and plugged in to reset the LTFT tables.
Started the engine, hit the reset fuel trims and it ran better for a little bit then the trims came back up to stupid high levels.
Then I noticed the injector disable buttons that you can turn off each injector individually. I went through all 8 and on 3 or 4 of them it made no difference in the way the engine would run with the injector disabled. the others would noticeably change the idle of the engine. I believe this is where my problem lies with maybe 2 or 3 injectors not firing on bank 1 and the other injectors flooding the engine to try and keep up.
I will do some deeper diving into the injector wiring tomorrow. if all the plugs are solid, I will pull the injectors themselves and test them and maybe soak them in some injector cleaner.
At least you have a target.
Your idle is really high (950 and for the whole table?) for a mild cam 700 rpm 725 tops at operating temp. You disabled the Idle>adaptive idle airflow ? Hi/Lo Advance and idle spark advance is pretty high they do not have to be the same *, one is closed throttle (usually 20* is plenty) and one is on the gas. You may have hanging idle issues goosing it and back to idle but at 950 it may not be seen. I suggest lowering the under/overspeed tables multiply by .75
Honestly I would do a compression test. 2000 5.3 Gap at 0.0040-.0045 It could be the coils are too weak for that 60 air gap and lean from misfire.
Whatever works though.
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