alright so here's the basics ... car was running fine, drove it for about 2 hours ... stop 3 times at different stores , shutting it off eatch time ... when i started it the third time , my idle was all messed up.

basicaly bounce around from 500-1500 ... will do it for a while but going higher and lower watch time, then completely drop down to 0 and stall ... tried driving it , no way i could , could regulate speed, kept jerking like if i was just learning to drive a manuel drive ...

so got it towed home, replaced the battery thinking it was that (battery was pretty beat and it is winter) , check the fuel pump and she's good. i'm not getting any Codes ... so anyone got any idea what this could be ?

thanks for the help.

BTW its a 2006 Cobalt SS Supercharged.

 

Are you tuned? When I got tuned my car did this and Vince had to make some adjustments.

 

yes we would have to have an idea if you have worked on the car recently and left an connector not properly installed for example. or a vacuum line off or...etc

 

well i'm modded ... all mods in VBgarage i only have a stage 2 tune ... and i haven't done anything to the car since this summer ... last thing i did i changed an HID Ballast and Bulb ... besides that nothings been done or changed performance wise ... no repairs either since may

 

Was it raining, or was there snow (water...maf) ? Was it humid out there, or anyways you woulda sucked some type of condensation through your air intake system?

 

well there is snow on the ground , but it wasn't a snowy day or wet day ... but i hadn't drive the car in 5 days , last time i drove it there was some water on the roads ...

also considered water in the gas ? ... since i did have a full tank of gas from the last time i drove it

 

Yes possibly, it if you drive the car without say a hydro shield to yeild water coming into the intake you will Skew the maf and in most cases clean it and your fine

 

alright so here's more thing i've noticed maybe should of added .... voltage goes from 12.4-14.5 ... AFR on my AEM Wideband just bounces from one end to the other ...

stupid question probably , but what would i use to clean the MAf?

 

There are off the shelf MAF cleaners you can buy at any auto parts store. Really though the key is to get the MAF dry. If there is any moisture on it, it will read incorrectly and can cause the bouncing idle revs you are seeing. Note that the MAF is just one possible cause.

 

Wipe it with alcohol.

 

what i'm thinking now , possibly Fuel Injectors, spak plugs or throttle body ...

 

I've had this happen once
idles rough sometimes when it's wet outside but it evens out after a second

Water in intake and dirty ass wet maf caused it

Just got a hydroshield, still gotta' clean the maf

 

My cars idle started to bounce shortly after I got it. After some searching on the forums I decided to try cleaning the TB. It didnt even look dirty when i got it off but i decided to clean it anyway. (note i took it right out of the car, 4x 10mm bolts and a few connections)
Anywho, cleaned it up well with some tb cleaner and a rag being careful when i was opening the electric throttle and put it all back together and volla, my idle was perfect again.
Its free to try anyway, right?

 

this thread might help

https://www.cobaltss.net/forums/2-0l...inally-116051/

 

Clean the TB - that is super quick and easy so you can get that done and either have the problem gone or you have ruled out another variable.

Have you checked the MAF and made 100% sure that is not the problem? A lot of us have had this behavior due to a wet MAF. The symptoms you described (exactly - car would rev itself and was basically undrivable) are what I had on a very raining day last year. I took the intake apart and there was visible moisture on the MAF sensor. Some cleaner and some light heat/air flow to dry it out and everything was good as new.

 

What he said

 

alright so ... clean the throttle body ... cleaned the MAF sensor ... still same problem

also notice that i'm cutting out at 3500-4000 RPM , should be 7000

another ideas?

 

Dude, I got the same problem, I've posted it a number of times and I also cleaned my TB and it did Help a Little but it still does the Idle Bouncing and occasionally stalls at stop lights etc. I'm gonna try cleaning my MAF this weekend as well, I've also had my Tuner look at it and that didnt do much either. If cleaning the MAF dont work I'm just giving up!

 

For the most part I am mostly stock and I am having the same problem.. It's annoying it seem like it get worst with the heater on or ac. I'll stop at a light and it bounces and if it bounces enough it will stall out and I look like a retard that cat drive lol