Fuel trims all messed up

[itsforsale2]

I am working on an LS swapped car that is having a problem with one side of the engine shutting off. Here is a little background information. The donor engine and trans came from a 2013 silverado. The computer was originally flashed with your standard unlock VATS and remove emission tune. (Not by me). I havnt burned credits to tune this thing yet. I have a couple idle tune logs that I have attached below. When I looked at the fuel trims one was way positive and one was way negative. So I assumed they were plugged in bank 1 in bank 2 and vise versa. I switched them and it appears that nothing changed in the log. So I am a little stumped. Can someone take a look at my logs and the tune. Maybe I am missing something or they were right orgionally. Thanks in advance.

The 6.0 has a ls3 intake
A cold air intake
longtube headers



67 Camaro Bank seperated fuel trims.Layout.xml

before o2 swap.hpl

after 02 swap idle only 2.hpl

camaro origional.hpt

[5FDP]

Log the o2 sensors and add the injectors. You have the fuel trims but there are no o2 readings to watch to see what the MV are doing.

Test the circuits for each and make sure they are working within specs.

Past that though, fuel trims are still going be whacked because the LS3 intake is no where near close to the size of the large truck intake but they should be close to each other. Everything will need re-tuning.

[itsforsale2]

Log the o2 sensors and add the injectors. You have the fuel trims but there are no o2 readings to watch to see what the MV are doing.

Test the circuits for each and make sure they are working within specs.

Past that though, fuel trims are still going be whacked because the LS3 intake is no where near close to the size of the large truck intake but they should be close to each other. Everything will need re-tuning.

Thanks I will look into that and report back.


I have the STFTs logged bank 1 and bank 2 separate. Bank 1 is showing trims as positive and bank 2 is showing trims as negative during closed loop. I dont know how the intake will affect it bank to bank I assumed the trims would be out of wack with the headers and intake just not one positive and one negative.

[SultanHassanMasTuning]

stick a wideband and OPENLOOP it

make sure there is no emissions test in customer state

as mentioned log Mv and injpw

[itsforsale2]

I havent been able to get back to the car till this evening. So far her is what I have and its pointing me in the direction of a wiring mess up. Here are my most recent logs. The car just wants to idle pourly. It will idle but it has a lumpy idle like it has a big cam. The owner and me both would like a smooth idle and I believe that is something that can be achieved. At this point the thing I have noticed in my logs is the b2S1 mv are not switching. It is stuck at 1,277. To me this point to a wiring problem or possibly a bad sensor. I plan on installing a wide band before driving to nail this down. Are there any tutorials for tuning this ecm?

camaro idle log.hpl

camaro origional in progress.hpt

[SultanHassanMasTuning]

as mentioned before, openloop the car and be done with it

[jsllc]

I would go find a stock tune for this ecm O2s seem to be changed in the tune and not correct.

[itsforsale2]

Thanks.

I will look into it. I have a couple that i can compare this one with.

What part of the o2s seem to be incorrect?


I also plan to run open loop and log error with my wideband.

The gen 3 systems I have down very good. The gen 4 with the VVE is tougher at first but im getting it.

I noticed you're in Bozemen. I'm in Missoula. Small world

[jsllc]

VVE is not SD. Will never be accurate. It is a close enough is good enough tech. Meant to be backup to MAF. You can run MAF without trims as well. On the parms best to compare to stock and make sure of ALL of the "magic" changes someone has made. Including disabling engine codes. Only a few reasons for this. Less fuel pressure on one side, less spark on one side, less compression one side, bad info for ecm decisions. Bad info comes from bad user input or bad sensor input. Usually a bad sensor will trigger codes. Unless of course a user said to ignore them.

Only a short 200 mile hop between us.