Not sure if you are looking for advice or not.

Comments:
1: Just because there is no loss of coolant, doesn't rule out the head gasket.
2: Including the CEL code is part of the diagnostics - and was not included.

 

But, you seem to have 3 bad cylinders. That is a bit odd. #3 seems to be always the bad one, but most people have reported that as the ONLY bad one. Could be you didn't do the test right?

As Whopper was saying, look for bubbles in coolant and/or collapsed hoses on cool morning. Sometimes the head gasket failure goes the other way. But, you gotta do the gasket if you do the head.

OBDII code would be lots of help! Could be something completely different, like a vacuum/exhaust leak.

 

I just stumbled across a thread from August last year (last post September last year)- this is a continuation of it, and therefore we start from the very beginning in the diagnosis.

I'll see if I can merge them together, but may have difficulties doing that due to being on a tablet.

 

Is this the thread you're referring to whopper?

https://www.chevyhhr.net/forums/showthread.php?t=47388

P.S. Ignore the unneeded link above gentle readers.

 

Done - thanks 843de. :)

 

Cool Beans! And job well done!

I edited the original thread title to "#3 misfire & compression test", that might bring things together for continuity.

 

It's always nice to know the whole story and time period.

From what I've read, looks like it's time to pull the head and see what's wrong in there.

(unless someone did an inaccurate compression test as mentioned before)

 

Context is everything, and the fun job of being on the staff here is chasing down threads and assembling them into contiguous units.

That's why our Moderators get touchy about having multiple new threads started on the same issue.

As far as the OP's HHR is concerned, you're on track George with either a faulty compression test, or biting the bullet and pulling the head. Sometimes you just have to open an engine up, there's no way around it.