My Mom's HHR has a problem with the engine stalling. It's a 2007 with the 2.2L. 50K miles or so.

It only seems to stall when the AC is on and she stops with the car in gear. It would happen maybe once every 3 days or so. I replaced the air filter (very dirty). Still occurred. I very thoroughly cleaned the throttle body. It didn't stall for a good 2 weeks, and we thought it was fixed, but then it happened again.

The check engine light does not come on, so I doubt there are any codes.

Any ideas? Do these cars have an actuator to bump up the idle when the AC is on?

 

I know the engine should compensate for the A/C when it is engaged, I'm not 100% sure if our cars have an Idle air control device or not..thats how the computer knows when the car needs more fuel to compensate. I would try something simple first...Does your car seem to idle rough? Maybe fuel injector cleaner will solve this?

 

Take it to an auto store. You can get a trouble code without a CEL.

 

You may have a bad throttle body. Being a 2007 you may be out of power train warranty, but if not, it's covered.

 

i am having a similar issue. i have an 06 2.2. I went to the auto store today and had a check engine light on it gave me the code p0133 if this is the same code as the 08. then it is saying my o2 sensor was slow to respond so i reset the code to see if it would come back on. now when at a stop the car just shuts off all the dash lights still stay like it is still running.

one thing i ask is an 06 p0133 code the same as the 08. i am thinking maby a clogged fuel filter could i get that p code form that?

also it idles rough with the a/c on air filter is fine.

so far an 06 with 40k on it i have replaced thermostat, rear hatch latch, power steering motor should have been recalled with the others. next time no first year run cars give them 2 years to figure things out first i love the car but i do work on it like it has 100k+