[Rhino8123]

Car: 2011 Cruze
Back story: My wife has been driving this car, and within the past week she's been noticing a burning smell when stopped. I was thinking it was probably an oil leak or something, but I drove it this morning and found otherwise. It doesn't really smell like burnt oil. It is a burning smell, but I don't know how to really explain it. I popped the hood when I finally stopped, and I noticed that this part (sensor) in the picture below was smoking and it is the smell that we've been smelling.

Does anyone know what this part is, or why it might possibly be burning/smoking? It's located on the front of the motor.

 

[mechguy78]

That would be your pre cat oxygen sensor

 

[Rhino8123]

Thanks for the response! I realized it was probably an O2 sensor after I posted. I'm thinking that somehow there's oil leaking onto it and it's burning off. I couldn't imagine that an O2 sensor would start smoking or burning for no reason.

 

[carbon02]

The heat wrap material that appears around the blue wire of the O2 sensor appears to be soaked in oil. We need some more pictures posted to help us.

Google Cruze 1.4L oil turbo feed line. There is a write up on this forum with pictures, however a lot of pictures are not working because the hosting site is restricting free accounts.

The orange triangle is at the turbo oil feed connection. The round orange circle is over part of the wire protection that looks like this is soaked in oil. Then it's dripping down.

You have either overfilled a sloppy oil change, the oil filter canister off to the right out of the photo. Big black plastic cap, or possibly the oil cooler gaskets are leaking.

Google Cruze oil cooler gaskets on Youtube.. Take a view from the poster Ruva I think his handle was. Watch the entire video.. He shows what's behind that area that could be the source of your oil leaks. https://www.youtube.com/watch?v=qfP1BWcOwkk

 

[Rhino8123]

It just recently had an oil change, so I'll take a look and see if it's possibly overfilled. I think I recall seeing somewhere that it's supposed to be 4.25 Quarts of oil. Does this sound about right?

 

[carbon02]

4.25 quarts is the top of the stick. In many cases 4 quarts is enough.. 5 is too much.

Have you owned this since new? Someone replaced the turbo oil feed line. The 2011's did not have insulation on that line from the factory, but later part numbers did have the insulation.

What's the service history in this area?

 

[Rhino8123]

We purchased it used from a dealership about 2 years ago with around 60K miles on it. I don't think we have a whole lot of service history on it, but I'll see if I can dig anything up when I get home. I'm not sure if the dealership would have any information on it or not.

 

[ChevyGuy]

Someone replaced the turbo oil feed line.

Replaced it or added insulation? It doesn't look quite "factory" to me.

 

[joes74challenger]

My wifes 2011 had a burning oil smell at stop lights off and on for a few months. Took it to the dealer they originally guessed oil cooler. Then after it got worse and we knew the third party warranty company would cover it we took it back. They then called the issue a leaking oil pan gasket, intercooler charge pipe. I asked why the diagnosis changed and then received an answer of well he didn't really know the fist time around. end result was the intercooler feed pipe being the cause apparently.


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[Rhino8123]

I'm going to look at it first thing tomorrow morning, but I did manage to snap a few more pictures. I didn't notice any oil leaking from the lid of the oil filter area, but it does look like a leak somewhere in this area. The heat warp/shield on one of the hoses is saturated in oil.

 

[carbon02]

Replaced it or added insulation? It doesn't look quite "factory" to me.

Not only did the factory add insulation to the revised part, but they also changed the "flange" connection that's shown in the picture. It's a much bigger head on the end of the revised oil feed pipe that's shown in the picture than the original 2011 early 2012 part. The head of the turbo oil feed pipe that is going into the oil cooler is shown in the picture.

It's that dirty insulation that appears to be on the O2 sensor that looks like it may have once been soaked in oil. That's fabric though, so getting it dirty once, and cleaning up your mess, would still show dirty insulation. Just rule that out as a source for the leaky oil.

Oil and Coolant Leaks are going to be a mess on this car as they age. There's simply so many connections that most other non turbo car's don't have. Oil cooler lines, turbo feed lines.. Even the automatic transmission has both the standard radiator cooler and a factory installed actual auxillary oil cooler.

 

[carbon02]

Ok-

I think your problem might be the oil pressure sensor leaking..

That dirty insulation may not be on the O2 sensor wiring. That's the area of the oil pressure sensor.. Pull that dirty oil soaked insulation back. Don't cut it off. That's an extremely hot area, and you want to keep that insulation on there. It's a wire going to a sensor. That sensor is in direct contact with Oil from the oil filter housing/oil cooler.

You can see the oil filter cap in your second picture towards the top. It's the black plastic thing with the nut molded into the cap. Remove that cap and allow air to enter the oil system and drain the oil down into the pan the best you can. Then you maybe able to remove the oil pressure sensor without it dripping all over the place.

Rockauto.com has pictures of the oil pressure sensor so that you can see what your looking for. Unscrew old and install new. I'd try that first.

Parts probably under $30.00 and you can do this. 24mm socket for the oil filter cap if you want to open it.

Also in your second picture, where you see the GM logo. Take a rag and some cleaner and get that aluminum nice and shiny. Then start the engine and possibly drive it and look for leaks. It could be the oil filter cap leaking down that aluminum housing. Clean all the way around the housing where the GM logo is. There's an o-ring in that cap, that should be changed at every oil change interval.

No question most tech's change the ring. The problem is the tightening. That cap has a 24mm head on it. Most 24mm sockets are 1/2". The plastic housing takes like less than 10 ft/lbs of torque. All you have to do is bottom out the o-ring and it's sealed. You don't have to go crazy. Crack the cap or strip the threads in the cap, and a new cap is required.

There's a Dorman product under oil caps in the Rockauto catalog. You can get a 3/8" extension with a U-Joint along with the socket down in there fairly easily.



Good Luck and keep us posted.

 

[Rhino8123]

It definitely looks like the oil pressure sensor is leaking. I pulled the shield back and it looks like oil is seeping around the sensor. The heat shield that I pulled back is saturated with oil, and it's coating the cables for both the oil pressure sensor and the O2 sensor. I'm going to replace the oil pressure sensor tomorrow. I'll clean everything off and drive it around to see if it does it anymore. Hopefully I'll luck out and it's just that sensor and nothing else.

 

[Rhino8123]

Update:

I changed the oil pressure sensor and cleaned everything up. We drove the car around 100 miles or so, and I can't find any indication that there's anything leaking. I believe this may have fixed my issue. We no longer get the burning smell either, so I believe that cured my problem.

Thanks for the input from everyone. Y'all were a big help.