I think I've searched for hours and hours for help with this issue, and while I found some good info, I'm still at a loss.

I have a 2007 HHR LT 2.2 with 72,000 miles on it. The last time I changed the oil, I only got something like 3 qts back out. Maybe 1500 to 2000 miles after that oil and filter change, the car starts making a loud noise that sounds something similar to when a soda dispenser runs out of syrup, if that makes any sense. I remembered my mom's car making a similar noise when it was out of oil because where she brought it for an oil change messed up her oil pan. So, I check the dipstick, and it's dry. There's never been oil on the floor, there's no oil stains on the oil pan or filter or anywhere else that I can tell, and we've had snow here for awhile and I'm not noticing leaving a trail of oil. No burning oil smell too. I put 4 qts in and stopped there because then the dipstick looked like there was too much oil. Anyway, that took care of the sound I was hearing, until I was traveling out of town.

While going around 60mph on the highway, I briefly heard what sounded like what I heard before, but it sounded more like a rattle or bad fan. Stopped, checked the oil, oil was fine. I resume traveling and then when the weekend was over I drove about 2 and 1/2 hours home around 70 mph the whole way without a sound.

I made an appointment with a mechanic because I was worried about engine damage, even though outside of that sound on the highway, the car was running well. He calls me up when he's done and says that the engine looked fine and there will be some oil consumption, but there was no damage that he noticed. He also mentioned a check engine light was on, which was strange because the light wasn't on when I left the vehicle there overnight. Since then, the car drives ok, but when I stop at a light or stop sign, it has a really rough idle that feels like someone is shaking the back bumper. When it idles like that, a sulfur smell comes out of the exhaust. I took the car to Auto Zone, and error code p0016 comes up. I remember from reading here people having various issues with that sensor. After a couple days, the car starts having a hard time starting up too unless I step on the gas.

So I replace the crankshaft sensor underneath the oil filter housing, I replace the camshaft position sensor on the front of the engine (repair manual showed only 1 camshaft sensor on the 2.2 model), replace the spark plugs, and there's no issues with the hard start, but the CEL is still on and the rough idle is still present. The car is also still driving fine, until I stop or slow down to a near stop.

I'm at a loss for what's going on here. I would think that if it was the timing chain, there would be other issues present, especially while the vehicle was in motion. However, changing the sensors didn't seem to help anything, but I haven't reset the computer, or at least I think I haven't reset the computer. I mean, I had the battery disconnected for 4 or 5 hours while I worked on the vehicle. That should reset the computer, I would think, but I'm no expert. The rough idle with the sulfur smell and sputtering sound out of the tailpipe while the car is parked don't sound related to the p0016 code. I also have no idea where the oil is going in this car, but the oil I put in the last time is still there. I'm really hoping someone here can help.

 

Need more info:

Did spark plugs show "oily" ?

Is your antifreeze still Clean, & not mirky looking from oil ?

The sulfur smell could be the Cat converter getting plugged up.

Code P0016= CKP-to-Intake CMP, correlation problem.

Our engines are "intereference" engines, if timing chain jumped, I would say valves would meet pistons in a bad way..

Edit: unhooking the battery won't clear a CEL, either run it for 80-100 miles or have it cleared, & see if it comes back on.

 

sulfur smell will come from bad fuel mixture too...like limp mode..

 

Spark plugs were not oily. Pretty worn, but not oily.

Antifreeze is clean.

Something else I forgot, when the car does rough idle at a stop, the headlights practically flash from the idling. They don't go all the way out, just dim, but it's like a kid at the dimmer switch sliding the damn thing up and down repeatedly.

So you don't think it's the timing chain then?

 

Low rpms for rough idle can cause low alternator output and dimmed headlights.
You may have fouled an o2 sensor with the extra oil burning in fuel, and now that emission control issue is causing the rough running.
Maybe valve guides... or front or rear main seal.....I have leaky oil cooler lines on my express and never leave a drop on the street. Only blows away while driving.
I switched to high mileage oil as its supposed to have more zinc to swell seals..etc.
Check all around the bottom of the engine, and if necc, orange blast the engine and look for a fresh oil stain after running for a while....Its going somewhere.....into the combustion chamber, or outside the engine. My guess is the former.

 

Should probably take it to a real mechanic ! What mechanic gives a car back and says "oh by the way your engine check light is on" .....

the least he should have done was checked the code, remedied the issue and then cleared it .....

sounds more like a really old mechanic or a tech in training .....

Best-O-Luck,

 

What was the end result here? Just stopped after you put in the 4 qts? Personally, since you lost oil twice and possible overfilled now, I'd dump some seafoam in the crank, drive it for 50 miles, and then do a oil change. You've lost a lot of oil for some reason, I'd want to know why.

How long did you let it sit before you checked the oil? (thinking still, overfilled)

This entire part has me scratching my head. You take it to a mechanic and he doesn't even check the codes with a CEL on? But says it's a-OK, and consuming oil.


Have the codes checked again and have them cleared. Auto Zone can do this also. Rough idle can be fuel or fire. Could still be coil pack, ignition module, IAC, etc. But you need to find out what instead of just throwing parts at it.

If your CEL is still on, there is still a code there. Have it check, and then reset.

 

Take it to a shop or mechanic that will actually help you.

Losing oil. Either it leaks it or burns it.(pushing oil into the coolant would be a leak).

"IF" you ran it that low on oil, it's just about a guarantee that you have done some major internal damage.

The fact that it has run that long after topping off the low oil, sounds like it wasn't really as low as you thought. It may be over filled at this point.

 

I apologize for the confusion because I was trying to keep my post as short as possible. I stopped at 4 qts because I was worried about the possibility of there being oil in there and overfilling the tank. At about that point, I checked the dipstick and the oil level was near full. After driving the car around for awhile and coming home, I checked the oil again, and it was just over the full point, maybe even more than that.

After that is went I went 2 1/2 hours up to Lansing, MI. During my few days there, while on the highway is when I had that noise pop up in the front end again, but only briefly. I pulled off into a gas station right away to check the oil there. I checked the oil a few times over a 5 minute period and everything looked ok.

When I got back home, and this is now maybe a week ago or so, I took my car in to get looked at. The mechanic actually thought my oil went dry from before because I went 9000 miles between oil changes. I left an old oil change sticker on my car, which is what drove that belief. He kind of shook that off and still seemed of the belief that I went a long time between changes and mentioned the bit about oil consumption, which sounded ridiculous. He also brought up the CEL, but didn't go into that any further. He did say the oil was dirty, and so I asked him to change it since they were running a special.

When I picked up the car, he told me to bring it in if I heard that noise again so they could listen to it right away. I was a little surprised he didn't check the code on the CEL, but I thought that he figured it was on when I brought it in, even though I said it wasn't, and since I didn't mention the CEL, he didn't bother checking it.

This place was recommended to me by quite a few different people and it's one of the more reputable shops in town. I'm also not very confrontational, but I'm a little upset that all of a sudden, after leaving my car there overnight, the CEL comes on and it idles like I have hydraulics installed. I'm trying to think of a way to raise these concerns without being accusatory. I would also take my car somewhere else, but some of the larger shops in town that have been around for awhile have performed questionable work on my cars in the past.

At this point, I guess I will just take it to Auto Zone to clear the code and see if something different comes up. I should also note that I tried fuel injector cleaner to no avail. I may as well have flushed a $5 bill down the toilet. Thanks for all of your suggestions though, it helps.

 

I wasn't talking about putting the seafoam in the tank, but in the crank to clean it out some. If you do have a leak, it might point you in the right direction. You might have a passage that's clogged and they could cause noise if oil isn't getting where it needs to be.