anyone just wanna blow up there damn cobalt sometimes! holy crap. any ways i had this damn problem for like 2 months and its driving me nuts. the car shakes when your going in first, shift from 1 to 2,and when u shift from2 to 3. makes a jerky accel like its cutting out something, looks like i dont know how to drive a stick. and not just a lil bit i mean bad! i have been trying to get a trifecta tune(dont even get me started on them) but vince said it was the car pulling timing cause my ic pump was bad. ordered a pump from ottp and told me every week " oh its in next week". not i waited 2 months. finally got the pump from yates and finally logged my damn car and vince is saying the logs look perfect, even though its still doing this and the bumper is black and was fallowing the car the other day and it pours smoke. is vince nuts and is it to rich or can it be something with the car itself???

thanks guy any info will help, my cobalt is bout to be pissed on and blown up

 

Have your tried cleaning out the Throttle Body? I do this every year and it helps make the car a little smoother and idle much better. Maybe take it to a dyno and see what the Air Fuel Ratio is if you don't already have a wideband?

 

Could be a clogged cat. Any thing else should set a code.

 

just cleaned the tb like 2 months ago. checked the plugs, maf sensor, injectors,filter. if its a clogged cat what do u? how do u clean it out?

 

You replace it or gut it. There is no cleaning it. You can remove it and look at it.
The honey comb should be able to easily pass light through it. You cand also run water through it. The water should very easily flow through it. Its usually pretty easy to visually tell if a cat clogged.

Bad


Good

 

but would it make it smoke and make the ex. tip really black? and what else is weird is sometimes it doesnt do it all, sometimes so so and other times the jerking is rediculous? wouldnt a clogged cat so it cosistently? all the time in every gear, and wouldnt performance drop? i hope its not the cat i just barely got the zzp dp with high flow cat

 

Yea what year LSJ? Ya know they had a recall on their cat's back a few months?

 

Its possible the cat caused the smoke. If some of the catalyst shot out. It should lower performance and it should be in all gears. Your engine mounts all intact? Have you checked the car for dtc's? Some codes wont set off the MIL right away.

 

its an 06, and i heard bout the recall, its a zzp dp and cat, doesnt matter. i checked the mounts but its not shaking because of them. its 100% for sure the motor/etc, and im assuming if it was a code or something it would show up on my tuners software or on the logs to trifecta. lol this is y its driving me nuts.

 

If its engine related it should show up on the in the data some where.

 

I don't know if this is What you are talking about. Any time when I give her gas I get a very hard jerk or let off the gas she jerks back pretty hard. Mine doesn't shake in the low gears though... Thought maybe it was a bad mount but they all seem fine.

 

yea i got this problem too. getting it to not jerk in 1st-2nd just takes practice, now i got that under control, but often times like in 3rd gear just cruising it seems like the car def. cuts out on me momentarily with no rhyme or reason. i just put in the ottp trans mounts so i dont think mounting is the issue, just got my cat replaced 2 months ago, cleaned my tb, so idk what to do now *throws up hands, says **** it, and walks away*

 

some aftermarket intakes and incorrect maf placement cause symptoms like this.

 

I guess I'm not the only on either..

 

Mine did this, but high iat2's I think are to blame. It won't even rev, and trying to shift it dies. Still no clue why. I've not had my car for 3 weeks, so no testing

 

Mine does that when I **** up the tune trying to get it perfect, especially the coast down tune. I just pop out hp tuners and flash back to a tune I know worked and try again. I would log you pedal sensor, I have a feeling that could be giving a dirty signal and cause that as well.