I am currently having problems with my 2009 hhr.

I have replaced the spark plugs, the fuel filters and injectors. (well my husband has) and the service traction and esc light is still on and the code p0302 is still on.

If anyone could please give me any advice I'd greatly appreciate it.

 

Next step would be to do a compression check.

 

got it. will try that next. thank you

 

Just to be sure. You did clear the codes after replacing the parts, right ?

If you didn't clear them, it could possibly be an old stored code that hasn't been cleared by the computer through key cycle time.

 

yes, we've cleared the codes after each job. it'll run without the service engine light on for a bit. but once i'm at a stop light, my car will start to stutter and then that's when the check engine/service esc comes back on.

 

CHANGED THE FUEL FILTERS?????? There is only one, and you have to remove the gas tank and replace the fuel pump to do it (not an amateur job). I wonder what you actually mean?

 

correction, sorry. air and fuel filters. my brother in law is a part time mechanic full time welder and has all the equipment. the service traction/esc will come on when i'm at a stop light and it will start to stutter. when i'm driving at a normal speed the service traction/esc light doesn't come on.

i'm to the point of just either going to the dealer (i just don't want to pay dealer prices) or to a reputable mechanic so they can really take it apart and see what the problem is. i'm just worried that's all.

thanks again for all the help. i'm at a loss and my husband thinks he knows everything, so i wanted a second opinion.

 

also, it will only stutter when my a/c is on.

Here's what's happening. If i'm at a stop, my service traction/esc light will come on. If I'm at a stop and my a/c is on, the service traction/esc comes on and my car starts to stutter.
when i proceed to drive after the light comes on, my car will hard shift or jolt when gears shift.

 

As firemangeorge mentioned, you need to get a compression test done on the engine to check the health of the valves and the head in general.

 

I give up.