Hey everyone, I've got an 04 with m62, 3.0 pulley, lsj pacesetter header, full 2.5 exhaust, intake, front mount h/e, gm reflash. The car has been running a little funny lately, and seems to be on the leaner side than it's ran in the past. I do not have a wideband, only a narrowband. I know these are ridiculous, but I can tell the difference the car is running even on the narrowband. It's not like it ran a few years ago shortly after I supercharged it. Here and there i'll get a putter after putting in the clutch from decel, and sometimes when I start the car on a warm start, it will fire hard, then bog a bit, then back to normal.
I had a stock fuel pump go out on me about 2 years ago, maybe less, and replaced it with another stock, because I found it for 30 bucks, it was local, and I needed the car that day.
My question is, what should I be looking to upgrade to? I am on a stock fuel pump, and lots of people cant believe I still have the stocker in. I also have the injectors gm supplied with the supercharger kit, which I am also unsure of. Dont know what # they are or what. Would I screw up the tune, or anything if I added a walbro pump? Or bigger injectors? I am thinking this is the problem with the idle, is lack of fuel.
Thanks for the help!
Did you replace the injectors?
Yes, I replaced them with whichever injectors come in the supercharger kit for the eco. I dont believe the manual said anything about what size injectors, or anything. I could be wrong though. I am going to assume stock cobalt ss injectors?
kit injectors should be the stock cobalt injectors. you could upgrade to larger but if it's run ok in the past, i doubt that would be your problem (unless you've got a clogged/bad injector)
have you pulled the plugs to see if you're leaning out or if they might be fouled? when was the last time you changed plugs?
I did the plugs probably 6-7 months ago.. maybe? Some time around then.
I'll check the plugs tonight, and see what I find. I might just replace them anyways.
Would it be a good idea to put the walbro pump in anyway? I just dont want to screw up the tune at all on it..
Ditch the GM tune ASAP. With the mods that you have, your doing more harm then good to your car. HP Tune for the mods, then enjoy again
M62, 42's, ZZP 3", ZZP S3 H/E
214whp 190wtq
If you are running 36's, then a adjustable fuel pressure regulator could help you out. I will be running 36's or 39's with the ls1 style AFPR and meth, and will be fine. I have seen it done a few times, and one of my good friends was running 238 hp on a stock motor with 36's and AFPR, Meth and the cobra h/e setup all day long...never had issues.
