CubsFanCraig, has this engine ever overheated in the last 10K miles?

 

Not once. It's actually been a really reliable vehicle, up until now. My biggest complaint is a constant clunking and rattling noise when I hit most bumps that may be caused from an accident years ago that the repair shop claimed to not hear. Up until then, it was whisper quiet. Actually, my biggest complaint is that it handles poorly in snow and rain, but that's a tire issue more than anything.

As for the fuel injector cleaner, I know what you meant, but a bunch of people kept telling me to try that to see if it fixed the idling.

With the SeaFoam, I just follow the instructions on the website? Where would I then check for leaks?

 

Once you run it for few miles and then change it, along with a exterior cleaning of the motor. If you have an external leak, the wet oil spots will be the tell-tell sign.

I'd run about a half can in the block. You can dump the rest in the gas tank.

 

No need to dump any in the vacuum line?

 

Not at this time, that's for cleaning the combustion chambers, etc....

As Solman suggested, just in the crankcase thru the oil filler tube. To clean the oil galleys & passages, etc. Then as directed do a proper oil & filter change.

If you go get codes pulled, write any down & post them here..

Again, I don't 'think' your timing chain is the problem at this point.

 

CFC, I had the same problem and it was the timing chain, get it looked at before something really bad happens as described in the posts.

 

So annoying and it figures this would only happen to me...

The other day I had Auto Zone check the CEL and whatever was triggering the error passed and the CEL was gone, but the rough idle wasn't. I took the car to get the underbody washed, put in some Seafoam, made another stop somewhere, and when I re-started the car, the CEL was back on.

I went back to Auto Zone, they scanned for the error code again, and P0016 came up again.

Yesterday, I brought my HHR back to the repair shop that looked at my car from before. They had my car for two hours, running all kinds of tests on it and inspecting it. The problem with the car is...a complete mystery. When the car is being driven, the crank and cam sensors are synced up and there's no problems. However, it's when the car idles that the sensors are out of sync. Given the results of the tests they ran, they were pretty sure there was no mechanical issues with the engine/timing chain/tensioners. No problems with the oil pressure when the car is idle or when it's running. Their recommendation was to take it to the local GM dealership (who I can't stand) and see if they could look at the car since they may have run across a similar issue. At this time though, their conclusion was that something else may be wrong that's triggering this issue, but they aren't sure what that would be since everything checks out ok.

They also didn't notice any oil leaks, but I think I may know where the oil could have come out. I noticed this the last time I changed the oil, but the oil filler tube was loose and the rubber gasket between the base of the tube and the crank case could freely move, even if the oil filler tube was tightened down. There was also some black, dried up gunk around that area. It wasn't much though, as it was only on the crank case around where the filler tube was at, and there wasn't splatter anywhere else. So, that could be one place it's coming out.

Anyway, now I'll be headed to the GM dealership this week to have them look at the car. Hopefully they can get me headed in the right direction.

 

Hmmmm..only at low/ no loads..could be timing chain..arnt the tensioners oil regulated? may check oil press at idle (or the feeder hole at tensioner could be plugged), maybe adjustment is sloppy at idle and tightens up at higher rpms as oil press comes up..or if worn, at no load the chain is flopping around because of cam lobes/springs but tightens under load where the slack is all on the return side of the chain...just some thoughts

 

This thread has me a little suspicious. From the OP to where it is now just doesn't seem to add up. Not calling foul on this, but look at the info.
The original thread was about "no oil" "low oil" or having to add 4 qts. That in it self is a major,major problem. Now the statement is no real noticeable leakage area. C'mon. 4 quarts would leave a heck of a mess. What's the real story and answer to the oil issue?
Like I said before, If it was 4 qts low on oil, it should have done some major internal damage or even seized the engine. That low and you won't have any oil pressure.
Now the thread has gone to a worry about a CEL and idling issue. ?????
Personally, I don't even see why it's still running.
Anybody want to shed some light on this or try to fill me in? As of now I just don't get this story.

 

No, the tensioners are spring loaded. And sounds more like a smoothly running sewing machine noise, when bad.

The mechanic is full of (waste oil) if he thinks 9K is a long time between oil changes, GM says to go by the DIC which will trigger somewhere around 12K.

This is awfully low mileage for timing chain problems, but wasn't 2007 the year that had the bolt hole drilled too deep and caused oil throwing? I'd check the recalls and TSBs, maybe you are still in 5 year 100,000 drivetrain.