Hello, I am new to this site and I want to ask a question. I have been chasing a P0303 code on a 2008 HHR 2.2L, What I have done so far is: New Plugs, New Coil Packs, New Injectors, and New Intake Manifold and still getting a P0303. Any more Ideas?
Thanks

 

Welcome.
Seems you've thrown a lot of parts at it. Were you just guessing or have you done any diagnostics ? I would suggest a compression test 1st. If it shows cyl. #3 as being low, then a leakdown test to find the problem.

 

Yep, what FMG said

 

Thanks, Yes i did do a compression test and all cylinders was 130 to 150.

 

Have you removed and cleaned the fuel rail?

 

Was cylinder #3 lower than the others?

 

I have the same problem, but have not tried a compression test and haven't cleaned the fuel rail. Any other suggestions???

 

Welcome to the site.

Try those first.

 

to the forums!

You have tried spark plugs, coil packs, etc like the OP did?

 

Had the same problem, dirty #3 injector. Clean the fuel rail also as Oldblue suggests