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Discussion Starter · #1 ·
Last December I started to notice an occasional oily, gas smell coming thru the vents, only when the car has been idling for 30 mins and if I have just the heater going, no AC. It has happened a couple of times during the summer, but again only if it idled for 30 mins and the AC off.
I have been looking up information and I thought it was the OCC I have installed, but I recently discovered someone posted it could be the carbon build up on the valves being the culprit and time to get the valves cleaned. My car is a 2015 2.5. It has 41,XXX KMS on the clock, so alot of my driving is city, but I try to go for a highway run when I can.
Could it be the OCC causing the smell to come thru, or could it be the possible carbon on the valves, or could it be my lack of miles on the car?
Any help would be appreciated
 

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There can't be carbon on the valves only when the AC is off.
I think you need to run more tests to gather more data and narrow down the possibilities.
 

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Discussion Starter · #4 ·
I have no clue. Only when the heater is on medium and the car is idling for 30 mins. It goes away once I start driving.
 

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I recently had this problem on another make of vehicle, it was a cracked crankcase ventilation hose -I'd have a look at the hoses connected to the top of the engine.
 

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Reopening this thread:

I notice this as well on my 2015 sTouring with manual trans. 61k miles.

It almost smells like exhaust is coming through my vents sometimes when the heater is on. It isn't consistent, but I seem to notice it happens when I'm driving a little more spiritedly.

I've done a couple oil changes and I notice this still and I have less than 10k on my cabin air filter. Not sure what this could be.
 

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Reopening this thread:

I notice this as well on my 2015 sTouring with manual trans. 61k miles.

It almost smells like exhaust is coming through my vents sometimes when the heater is on. It isn't consistent, but I seem to notice it happens when I'm driving a little more spiritedly.

I've done a couple oil changes and I notice this still and I have less than 10k on my cabin air filter. Not sure what this could be.
Does it smell like rotten eggs with a hint of ozone?
 

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Nope, not as much of a sulfuric smell. Smells more like the heater is blowing in exhaust from outside but many times, the smell flows in when I'm on the highway on an empty road.
 

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Exhaust smell in cabin connected to heater vents connected to engine compartment connected to leaky gaskets and hoses....connected to the hip bone....seems like a good place to start. At this point wouldn't suspect a cracked manifold since most small manifold cracks seal when the engine heats up which is when you say you notice it with your spirited driving.
 
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