PCM reset

[alfienoakes]

I treated the car to a CAT back exhaust from Picadors (thanks Graham !) for xmas, but after putting it on the car sounds faster, but I'm sure it has slowed down. I'm hoping a PCM reset will sort it out, but I've seen conflicting procedures on the web. Has anyone done it to a 04 CV8 ?

[Dan_the_man]

I think you can pull out a few fuses while switching the ignition (more info on the LS1 forums) however you don't need to do this as your car will re-learn the new exhaust in time so it may be as easy to just drive it around for a while.

[GSE]

Ideally what you should do is connect to the vehicle ECU (or PCM) and reset the fuel trims. A GM dealer with "Tech2" (?) or anybody with HP Tuners software should be able to do this. If you're near the south East or London area I can do it for you.

If this is not possible, the ECU should adjust the fuel trims with time, but you will have to drive it some distance and vary the load/rpm of the engine. I would think that with just a cat back exhaust you'll be ok but I did have some surprises with mine.

I have a enlarged air intake, headers and an exhaust and I found that my fuel trims were miles off centre when I connected HP tuners. The ECU could not cope - some of the calibration tables (MAF airflow & VE) needed adjusting to suit.



>> Edited by GSE on Tuesday 28th December 23:38

[alfienoakes]

Cheers Guys. I've seen also seen an article saying that whatever you do, don't pull the fuse with the ignition on. I ordered hptuners last night anyway, so it should all become clear soon....I ordered the enhanced IO cable too, so now I have to get a wideband O2 sensor, has anyone used one ? I was looking at the PLX M-300, but there are plenty of others out there.
I'd like to get my power back soon, I can hear all the chocolate mice laughing at me !(for Barry Sheene fans :-) )