I drive an 06 s/c

Ok my car has been in the shop for quite some time now. Several problems they have found such as broken engine ground to faulty injectors. But still nothing has fixed the problem that i brought it in for. The Car studders really bad when its cold have a good 10 mins of driving it stops but still feels really slow. I have not dont anything to my car in the last 15 months modification wise. But i have the airbox mod, bolton muffler, and 1 step colder plugs. The dealership cant figure out whats wrong with it so any suggestions ?
Cat was replaced once after 4000 miles. And i have never had an updated tune.

faulty fuel pump, filter maybe? Did they check the pressures on your incoming fuel line?

put the stock plugs back in...you dont need one step colder unless your running more boost or nitrous

they claim they checked the whole fuel system..... i have 1 step colder plugs b/c of the extreme heat around here they helped alot and they have been in there for about 15000 miles

take your airbox mod off, could be your MAF

yeah i got my money on the MAF. but would that cause the vehicle to stutter?

yea of course it would cause it to stutter.... If its a dirty MAF then it could even not start, same exact problems they have with stage 2 ss/sc's that have idling issues because of a faulty or dirty MAF sensor

yeah i got my money on the MAF. but would that cause the vehicle to stutter?


Fowling plugs.

I would check the plugs and possibly replace them. There is no reason to replace your plugs with colder plugs unless you have mods that require it. The external tempurates do not effect the internal combustion tempuratures unless the car is overheating for some reason. You IAT2 is not going to improve from running colder plugs.

when the car heats up it runs fine ???? ima get new plugs and check that out

to check the maf, start the car and then unplug it, it should either shut off the car or run worse. If it keeps running like it was it mostlikely isnt the maf.

I'm betting plugs too...

my car had a surge on my rpms and my car was running like shit... then i put my stock intake on took the battery cable off for 5 mins then started my car my cars been running fine since then...

This car is a SHIT. Return this one at garage. COBALT is a car for asshole.

and you Mr Quebec... are a troll and have no place in this site.

I also own a 07 S/C. I have had a handful of problems with it nearly every month since purchase. I just had a faulty head unit replaced over the winter. Last month the dealer ship had mine in the shop for 3 weeks until they supposedly found a bad value guide and replaced the entire cylinder head assembly. This weekend the check engine light is back with another P0300 - Multiple/Random Cylinder Misfire(s).

Honestly, I love the car when it is running well, but for me that seems to only be about half the time. I advise that you seek a claim with the Lemon Law; if yours is as bad as mine. My arbitration hearing is in September. I plan on winning, given I have had uncalled for warranted repairs at least every 2-3 months if not every month. Then I’ll hopefully trade in my S/C Lemon for a new T/C model :cool:

i say air box mod w/ maf being the issue. also u might of sucked up a bunch of water via air box mod and did something internally. but i think it would of caused codes to pop up and what not... any CELS?