[carnewbie]

My Chevrolet Cobalt 2010 2.2 LT has been shaking and stalling when in idle. After reading multiple forums, I decided to try cleaning the throttle body. I took it off completely and cleaned it with throttle body cleaner. I also cleaned the air intake sensor with mass air intake sensor cleaner. After putting everything back on, the car displayed a message saying "engine power reduced" and it makes a clunking sound between 25-55mph. Any ideas on what could be the problem, one problem keeps happening after another! Thanks in advance!!

 

[Timswift]

I had to replace my throttle body after cleaning it once because i shorted it out , but what you can try to do is the relearn procedure which you can find online, hopefully this helps. Also always disconnect the battery before removing or installing or cleaning the throttle body.

 

[MP81]

Which air intake sensor are you speaking of? The MAP sensor?

The MAF sensor very likely might be the issue here. They're extremely sensitive, so cleaning it may have caused the issue.

 

[carnewbie]

I had to replace my throttle body after cleaning it once because i shorted it out , but what you can try to do is the relearn procedure which you can find online, hopefully this helps. Also always disconnect the battery before removing or installing or cleaning the throttle body.

Thank you! I did disconnect the battery before bc I read that it would help with the relearning procedure. I have been driving it around and it seems to be helping. Although, the car is having problems accelerating after being in idle. Also, the RPM jumps to 3000 when I turn it on, but immediately goes down and it doesn't jump around when driving. This is my first car and I'm still learning how it all works, so thanks for any advice in advance!!

 

[carnewbie]

Which air intake sensor are you speaking of? The MAP sensor?

The MAF sensor very likely might be the issue here. They're extremely sensitive, so cleaning it may have caused the issue.

It was the MAF sensor that sits in the chamber of the air intake. Is there a way to test if it has gone bad? Thanks!

 

[MP81]

It would be really difficult to test - you'd be looking at voltages and what not.

Is the car throwing any codes? I have to imagine it is, given how it is running.

 

[mitche]

double check all hose connections and electrical connections, it's possible you didn't get something tight. Maybe a vacuum leak. And the main hose on the throttle body.

 

[stower17]

I’ve been around these cars a long time, the best way to clean a throttle body is to leave the battery connected, removed the throttle body and clean it removed from the engine. Don’t move the metal throttle plate because the gears can strip.

Disconnecting the battery will reset the learned throttle values and can cause issues. When the ECM is reset it needs to get a baseline reading from multiple sensors (throttle body included). And when you cleaned the throttle body you are cleaning the gunk that affects air flow so there’s no telling how the ECM will be affected.

You should have codes, have you checked?

 

[CodyATE6]

Did you move the throttle plate by hand? It is said this can cause damage to the electronic throttle body or motor. The way I cleaned mine was using a scanner to open the throttle with the motor itself.

While that is possible, it’s more likely possible to miss position the intake tube onto the throttle body. The rubber boot sometimes will not seat and cause a gap. Even if it can be tightened down. Check that, I’ve actually accidentally done thing on this car due to the design of the intake tube.

 

[BlakeKirk]

You can buy a 50 dollar code reader at Walmart and it may help you. I just changed my throttle body today. It was having some high idle problems and I found out where the relearn setting was on the app. It fixed the problem instantly after the relearn process.