Guys,
this is my first post although the archives are full of repair info I normally use.

I have a 2008 HHR LS wagon with a 5 speed manual and an accumulated 319,000 miles. Last week after throwing a check engine light , it showed a " reduced HP " message. After a diagnosis at a local parts store , I replaced the #2 cylinder ignition coil. It ran fine for a few days but now has a stuttering miss at sustained speeds . it is irregular and also happens in low gear[s] accelerating away from a light or stop sign. I suspect an ignition problem but there is also a yellow residue [very little ] coming from the pcv valve connection to the airbox . I've had this "yellow snot" form in the oil filler tube for years but it is never in the oil at changeout.

Question 1 , what is a logical diagnostic trace on the ignition system back from the coil that might create the "stutter".

Question 2 , could the yellow snot be fouling the intake ?


Status now, waiting for engine to cool down to check plugs for fouling or indication of leaking coolant.

Thanks

 

What kind of diagnosis was done at the auto store? Did you have a CEL or other indication on the dash/DIC.

If you had the codes read at the auto store, what were they.......the codes, NOT the wording.

Codes are generally correct, the worded diagnosis is usually wrong. Remember the stores are in business to sell you something.

Anyway, if you have the codes, post them here.

 

The yellow stuff; is it the same color as your coolant? If you were using DexCool it would be orange, The green/yellow other stuff might show as yellow.

And, if it is dripping from the there the connections need to be tightened.

 

First code was a week prior PO302 Cylinder misfire #2 cylinder. Then after the incident P2101 ,P0102,P0113,P1516,P0300. I removed all the coils and put them back, checked all the plugs and put them back then drove straight to Autozone and the pulled the above codes ( after I got it running normally with the check engine light still on] then the check engine light went off and hasn't been back on. I replaced the #2 coil with a new one. runs fairly well except for the occasional "stutter" like a brief misfire .

 

A week after the coil replacement, I've suffered another "Reduced Engine HP" message and the car is missing again and won't drive as is.

 

That many miles, I would repull the codes AND do a compression test.

Fwiw. You used the term "reduced HP" in 2 posts. Honestly, I don't think the term "HP" is even in the HHR's computer DIC program.
Now, if you are seeing "Eng Pwr Reduced" then that is in the DIC programming.