Romulet

Hello,
I'm new to the forums. I have a chevy HHr 06, problem code p0302. This whole time it did not misfire or anything. This has been going on for quiet some time. I have replaced the ignition control module and spark plugs a couple of years ago and the engine light has gone out. Then the engine light would come back on and off intermittently. A couple of months back the engine line came on and did not go out. The check gas cap came on as well. Just last weekend I have replaced the ignition coil and the spark plugs and gas cap. I reset the engine code and it did not come back on.

My woman drove it the other day and the engine light came back on; now with code P0492. I checked it and it has to do with the emissions. I have replaced the purge valve canister because of the check gas cap and that is what the code is saying to replace and it was the cheapest part to replace; as soon as I replaced the canister; I started it up and now it is misfiring big time. I checked the code and now it's back to P0302 code now with a really big misfire. The engine light did not come on until I drove it. Now the engine light comes on and it is blinking. I have checked the fuel injector by swapping them out and see if it changed codes but it did not. Right now I am at a stand still where I have no clue on what else to check.

I just hope it's not my engine computer.

What I have replaced so far.

Code P0302:
Ignition coil
Ignition module
Spark Plugs
Swapped fuel injector with cylinder 1 but it still had the same code after I reset the code. I checked the Ohms as well and they are both putting out the same.

Code P0492: check engine light did go out. After replacing this, this is when the engine started to misfire but this time more noticeably.
Valve canister

Help Please and thank you
Thomas Duffin

donbrew

More likely your head gasket or a burned valve than the ECM.

The P0492 is likely the purge valve, that's the one under the hood. The OBD2 monitor for the EVAP system can take 17 cold starts before it runs, so people usually think they fixed it only to have it return 2 weeks later.

You have thrown just about every part at the problem, now try diagnosing what's wrong
look at this link: https://www.chevyhhr.net/forums/how-...e-light-52828/

whopper

A blinking CEL means do not drive it, without causing further damage.

843de

X2...whopper's statement really needs to be in 48 point type and flashing on and off.

Never, but never, drive with a flashing CEL, no good will come of it.

Romulet

My car does not over heat and it is not losing antifreeze or anything. How can it run smooth but with the engine light on then swapping out the valve canister than all of a sudden you feel the misfire? I have been driving the car for a couple of years with the light going on and off. When I got the car inspected, it passed with the light out. The light came on and never went out a couple of months ago. When I replaced all those components, that is when the new code came out of the P0492. When I installed the new canister the light went out but the car is misfiring so bad, this time you feel it; it never did that with the other canister. Now with the original code back of p0302, I'm thinking there is something wrong with the computer. There is nothing else to change but the purge valve solenoid but again I have to wait until I drive it longer for another other code to come up but now I can't because if I drive it, the light comes on and blinks. I don't want to cause damage to the catalytic converter. This is the only car that I have worked on that gave me sooooo many problems. Unreal.

donbrew

Did you bother with the link?

Oldblue

I Googled and got a list from Snoopy here and wondered

code P0302 may mean that one or more of the following has happened:
•Faulty spark plug - you changed them
•Faulty coil (pack) - you swapped them
•Faulty oxygen sensor(s)
•Faulty fuel injector
•Burned exhaust valve
•Faulty catalytic converter(s)
•Running out of fuel .... ??? would be from Evap purge valve solenoid
•Poor compression... from your description of it running well, I doubt it
•Defective computer ... try a reset after you replace the evap purge valve solenoid

you state you are waiting for the code again, but you seem to already know the part causing the issue.

donbrew

I put a lot of work into the link. It is also in my Sig. If you want to know anything about OBD2 ENGINE codes please read it.