I have a 2010 cobalt lt 2.2 liter. I did a recent transmission fluid change, it was all black and the shifting was horrible. I had to replace the o2 sensor behind the engine because it was shaking at red lights. Anyways i just installed a cgs axle back exhaust and my now my rpm cant decide if it wants to go up or down. It revs up and down over and over. I disconnected the negative side of the battery to reset the ecu and I've been driving it around a lot lately. My miles per gallon average went way down, from 25 down to 17. My car won't shift as well as it used to at all. I want to clean the throttle body to see if its getting enough air inside. I dont know if that will fix the problem though. Thanks for any info!
Rough idle after exhaust install
- Thread starter Squanto
- Start date
I doubt the axle back has anything to do with your issue.
Did it start doing this right after replacing the o2 sensor?
Any check engine light codes?
If I had to guess I'd say that your MAF needs cleaned, that's usually the primary cause of hunting for idle but see if you have any pending codes.
Also, if you decide to clean your throttle body, disconnect the battery and DO NOT MOVE THE BLADE BY HAND. I cannot stress that point enough, if you move the throttle blade you can throw the motor/sensor correlation and the throttle body won't work the same again.
Did it start doing this right after replacing the o2 sensor?
Any check engine light codes?
If I had to guess I'd say that your MAF needs cleaned, that's usually the primary cause of hunting for idle but see if you have any pending codes.
Also, if you decide to clean your throttle body, disconnect the battery and DO NOT MOVE THE BLADE BY HAND. I cannot stress that point enough, if you move the throttle blade you can throw the motor/sensor correlation and the throttle body won't work the same again.
Thanks for the reply!
The idling was a lot worse before i replaced the o2 sensor. It wouldn't accelerate at all even when floored. It had a similar problem before replacing it though. It would shake at stops and the lights would dim. Replacing it helped and it ran smooth.
No check engine light at all, but on the way home after installing it I got an SVC tire monitor light. I turned off the car and checked the tires and all was fine. I turned on the car and it disappeared.
It also has a weird smell coming from the car after installing the exhaust. It smells like propane, but i read it could be just the chemicals burning off the new one.
I was thinking it was the MAF sensor so I'll be checking that too with the throttle body.
The idling was a lot worse before i replaced the o2 sensor. It wouldn't accelerate at all even when floored. It had a similar problem before replacing it though. It would shake at stops and the lights would dim. Replacing it helped and it ran smooth.
No check engine light at all, but on the way home after installing it I got an SVC tire monitor light. I turned off the car and checked the tires and all was fine. I turned on the car and it disappeared.
It also has a weird smell coming from the car after installing the exhaust. It smells like propane, but i read it could be just the chemicals burning off the new one.
I was thinking it was the MAF sensor so I'll be checking that too with the throttle body.