[knipdlo]

Hi all,

I bought my 2013 Volt CPO w/30k miles at the beginning of December and so far it has been a great car/experience. I have lurked on here for years and I’m familiar with the issue of the ICE collecting road debris and then smelling funny when it runs for the first time until its burned off.. This makes great sense to me, and wouldn’t bother me if that was my issue. My issue seems to be getting worse- or it could be colder temps- the last few days being that its Christmas time, I’ve been doing a lot of driving beyond my EV range, and thus a lot of ICE usage. Tonight while driving home about 35-40 min at 75MPH with 4 people/heat running and 23˚F temps, we smelled *a lot* of exhaust in the car. I thought I smelled a little bit of burning oil the other day when the ice first started up and attributed it to the standard “engine hasn’t started in 3 weeks” thing, but tonight was pretty much unacceptable. I’m sensitive to smells and I’ve got a pounding headache now that I’m home. I was trying to ignore it in the car thinking I was just being sensitive/maybe we were following a stinky truck up ahead but eventually my mother whispered to my dad in the back seat about “is there a gas leak or something?” So its not just me.

The smell seemed worst and nearly constant at speed. It seemed to possibly go away when the HVAC was set to defrost, and seemed to come and go when set to Auto (probably auto-recirc cycling), but when on Floor only with no recirculate it was straight nasty.

I love this car but I can’t even handle car air fresheners without getting migraines.. so if this is a thing, it isn’t going to work out.

Did some searching and only saw stuff about burning off- anyone have any experience with rear trunk gasket issues or anything?

 

[Steverino]

The rear hatch my not be as tightly sealed as it should be, drawing in exhaust fumes. The hatch has two screw-in rubber bumpers. They may be screwed out too far. The hatch is closed and latched, but not as tightly pressed on the hatch gaskets as needed to seal the cabin from outside air getting sucked in. The screw-in bumpers can be adjusted by hand. Perhaps they were loosened when someone was towel drying the car after a wash.

 

[knipdlo]

Thanks for the reply Steverino- are these the black rubber things at the bottom of the sill, the top of the tail lights, or on the underside of the hatch lid itself? Car is under warranty.. should the dealer be capable of diagnosing and doing something about this?

 

[PrivatePilot]

Also check the little rubber gasket that seals the underhood area just above the firewall - this gasket contacts the hood when closed and keeps any underhood gasses from reaching rearward of that seal location which is where the HVAC draws it's air from.

If that rubber seal got bumped or dislodged it's possible you may be getting some exhaust from the engine area being directly sucked up by the HVAC. There shouldn't be much raw exhaust in that area unless there's a leak somewhere, but even the smallest exhaust leak can certainly bother you in a hurry if it's being blown right at you by the HVAC constantly.

And yes, check the rear hatch as suggested. Anyone who ever drove in an old station wagon as a kid with the rear window down knows all about how exhaust gets sucked back into the car.

 

[Mister Dave]

Here you can see the 4 stops for the hatch (one is missing top-right BTW just like on my car). I don't remember which are adjustable. The ones that are screw in and out.

 

[Prohidium]

There should be no exhaust smell other than if you were following another car that was spewing exhaust such as a bus or diesel or a 70's 'Vet. As others have suggested, check the seals around the hatch and doors but if you had a leak that was allowing that much exhaust smell, I suspect you would hear it as potentially significant wind noise in the car.

Can you hear any sort of exhaust leak from the actual exhaust when the ICE is running? Maybe turn the car on, pop the hood to start the ICE and then have a listen for any exhaust leaks. Next, take a good thick rag and try to cover the exhaust at the back and check for lots of pressure. It should resist your attempt to block the exhaust and should be putting out lots of pressure. If you can easily block it or if lacking pressure, look for a hole, a blocked exhaust such as a bent/crushed pipe or damage to the converter or muffler. If you try to block the exhaust and there is a hole, you may be able to see/hear/smell the leak better at a point along the exhaust. If any of the results materialize then you have an exhaust issue. A dealer trip is probably warranted if and you don't want to mess around with exhaust getting into a car!

You probably know this already but if not, the exhaust starts right at the engine manifold exhaust header on the engine, next the donut gasket where the exhaust bolts to the exhaust header, next an extension pipe, next the converter, next another extension, next the muffler and finally the tailpipe. A leaking donut gasket(a typical leak point) is usually noticeable in a regular ICE vehicle upon acceleration but maybe not so much on the Volt. A cracked exhaust header is usually quite noticeable as are most exhaust holes but again, the Volt ICE may not be as noticeable due to the way it operates vs. a traditional ICE when accelerating.

 

[JC Volt]

We just had a very similar/same problem. We were on a long road trip (unusual for us, usually local travel all electric) and had a lot of odor in the cabin. Didn't matter if ventilation was on or off. We opened the windows a bit which was better but still had some odor. Anyway, appears the problem was that at our last oil change at the dealership, they overfilled the oil. When the ICE was running for an extended time at highway speeds it expanded and overflowed from the filler cap area. We had a lot of spray in the immediate area and the heat of the constantly running ICE was burning it off creating a terrible odor that was being sucked into the air inlet below the wipers and blowing around the sides of the car where it was also entering through the windows when open. After driving like that for a day and a half (we had to get to our destination as long as the car would still run) we must have expelled enough excess oil that the problem resolved on its own but the spray on the filler cap and cool nearby areas was still visible. Checking the oil level with the dipstick still showed a bit above full. The whole experience reminded me of my Dad's adage "If you want something done right, do it yourself!"

 

[viking79]

I agree, check the oil level, if that persists the condition of the PCV system (crankcase ventilation), sometimes rubber hoses deteriorate and let fumes out.

Secondly, if it has been driven largely on EV, it might need to burn crud off. With a dead battery, park the vehicle in a safe place (outside with no people in it) and run "Mountain Mode" until it stops charging (like 45% or something). This runs the engine pretty hard and hot and should burn off anything that normal driving might not get hot enough to do.

If you smell exhaust fumes in the car, roll up the windows and turn the climate fan on full blast. That will pressurize the cabin and help push exhaust fumes out. If they are coming from the rear or maybe underside of the car. However, if exhaust fumes get worse, it is probably coming from the engine compartment, and then maybe need to crack your windows. Maybe try the fan on recirculate or turn it off entirely.

Either way, exhaust fumes can be a serious health risk (primarily CO poisoning). My Volt will have them for a short time when it gets cold and I haven't run the engine much, but a nice run in mountain mode or even on highway to burn crud off and it is fine. Like starting up your furnace each time in the fall. Persistent exhaust fumes are a problem.

My brand new Clarity PHEV smelled the same way until I ran it on gas for a while. What does your lifetime MPG indicator show on the dash? Might give a clue on what percent EV it was run. 250+ is a sign it was only run on EV, and even 150 mpg means the engine isn't run very often.

 

[granbo]

Had the same issue after I purchased my 2014 Volt two months ago with 37k miles.
A new oil filler cap from the dealer resolve the problem. $17.00

 

[volt spain]

Finally getting solutions, do not overfill the oil, new oil filler cap, all makes sense. I wonder if the same engine in other cars like the CRUZE have similar smell issues. My Volt 14 only gets the "smell" with the heat blower in high , and when using Mountain Mode. I guess higher temps and pressures increase oil/gas leaks.Will try a new oil filler cap. Thank you granbo, and welcome to the Forum.

 

[!arry4pyro]

I had this problem, my dealer traced it to a cracked oil filled cap.

 

[Aseras]

Also, the volts did NOT come with a cabin air filter from the factory. Unless someone put one it, you likely don't have one. It's behind the glovebox. There's a little slot/door you open to insert it.

https://www.amazon.com/dp/B007QC1TIM/

Best $15 you'll spend on the car.

 

[MoveAlong]

Experienced this problem myself on my 2012. Dealer put too much oil in (I believe max capacity is 3.7 quarts). On a 400 mile road trip with some mountain mode usage, got the awful burning oil smell. Turned out that that the oil cap warped due to too much hot oil. It was very obvious, cap wouldn't seat and oil was sprayed all over the underside of the hood and engine cover. Dealer apologized and gave me a free replacement oil cap and new oil. Took forever to burn off all of the leaked sprayed oil though, even after they tried their best to clean it up. Moral of the story is to absolutely make sure there is not too much oil! On my last oil change, I told them to only put in 3.5 quarts and they looked at me like I had three heads. They will automatically slam in 4-5 quarts without thinking.

Sent from my LGUS997 using Tapatalk

 

[TripleTrucker]

My smell is definitely exhaust, not oil burning on a hot engine.
Dealer checked for leaks last year and found none. Odor came back again this year, so I'll try adjusting the hatch stops.
Anyone hear of a way to pressurize cabin to check for gaps in weather seals? I could swear I saw some kind of "smoke machine" that did this.

 

[Barry]

The HVAC air intake is right at the top edge of the hood, and although there is a rubber gasket between the engine compartment and the intake, it is not sealed well and air will pass. IMO, this is the most likely way you are getting the odor. I would start by opening the hood with the car turned on to observe the engine running. You might spot the issue. Look for exhaust leak.

Headache is a symptom of CO poisoning. Very serious risk with this problem. Don't drive it on gas at all until you get it fixed. If you do have to drive it on gas in an emergency, I would have HVAC off and in recirculate mode, with all windows fully open. That stuff is a silent killer.

 

[knipdlo]

Well OP following up after a couple busy and cold(er) 9 degree days with lots of ERDTT and running longer than battery range allowed:

Firstly, I haven’t had the smell again since Christmas night. Second- the car had a lifetime 129MPG when I bought it, and I’m currently at around 125/123MPG, I did not reset it, and with the single digit temps in Syracuse it’ll continue to drop for the foreseeable future because of ERDTT.

Second, I checked under the hood pretty decent, visually inspected the seals around the rear hatch and under the hood, and everything is where it should be and seems to be in good shape.

Thirdly- I’ve had cars with leaking valve cover gaskets in the past and this was definitely exhaust smell not burning oil. I think I smelled some burning oil/crud when I first got the car, but not since a long 1hr each way highway drive at 80mph with AC and 3 on board my first day with the car.

I have a couple of theories on what could’ve caused it on Christmas Day:
1. A piece of ice or a chunk of snow got in the hatch seal when opening and closing it and allowed exhaust from the rear of the vehicle to get sucked into the cabin.
2. The air pressure relief valves that are built into the car body so that you don’t pop your ear drums when someone slams a door are faulty/were frozen/had ice or snow inside them sticking them open.
3. A underhood exhaust like at specific temps or loads which was getting sucked into the HVAC intake below the windshield.

Either way, hard to trace in my case since it now seems to have resolved itself. I need to do a bit more full generator only driving, since mostly I’ve been in ERDTT the last couple days. IF I find that I have significant smell that returns with higher usage of the generator, I’d probably suspect a leak under the hood and traveling into the cabin through the intake.

I’m hoping it was something like ice in the seal etc. I love this car and I want to keep it for a really long time!

If it comes back I’ll post back in this thread and probably try to rig some kind of device to create suction in the car and do some smoke testing.

Thanks all!

 

[PrivatePilot]

Good to hear it seems to have fixed itself.

We are in ERDTT/sub-arctic freeze hell up here as well. Woke up to -27 on the thermometer this morning. My guess-o-meter is slowly creeping downwards in the last few days towards 35KM, about 20 miles.

 

[Mister Dave]

Either way, hard to trace in my case since it now seems to have resolved itself.

Sometimes it's a matter of wind direction. No car cabin is completely sealed off from outside air, or you'd eventually suffocate on a long drive. If your exhaust was blowing back on your car........ I've been in this spot more than once.