Oil smell in cabin

GJ1 · Post by **GJ1** » Sat Feb 27, 2021 4:05 pm

Hi all,

Just wondered if anyone has experienced this before or got any ideas.

My car recently went to an indy for an inspection and some other preventative work which included engine, gearbox and diff oil changes.

Ever since the car went in (about 276 miles ago now) there has been a strong smell of oil in the cabin whilst driving.

I've checked for any oil spill in the cabin (just in case) and can't find any.

I've checked the engine bay and have spotted what appears to be a small oil leak but I'm not sure if this is new or old. Has anyone had similar? What is the fix?

I'm also not sure if this is alone is enough to account for the cabin smell as would seem like a bit of a coincidence that it only appeared after its visit to the garage.

I noticed the smell in the cabin within 50 yards of driving today so the engine wouldn't even be warm enough for anything to heat up and cause the smell I wouldn't have thought.

I did wonder if some sort of filter hadn't been replaced which was allowing the smell to come through to the cabin. Not sure where to look exactly.

I don't feel like I want to go back to the indy at the moment because whilst it was in they damaged the bonnet which resulted in them arranging for it to be repaired and resprayed. I know it was there fault but at the same time I feel like they'd see me as a nuisance.

Any ideas/pointers appreciated.

Cheers

GTwice · Post by **GTwice** » Sat Feb 27, 2021 5:13 pm

It looks like a leak from the oil filler cap. Maybe they spilled some during the service. Could be also the valvetronic motor seal.
You get the smell because the oil is dripping onto the header, which gets hot almost immediately after starting the engine.

Remove the engine cover (it's just 4 small bolts) and you can be sure.

Thrustyjust · Post by **Thrustyjust** » Sat Feb 27, 2021 5:30 pm

Been suffering the same and this winter did a replacement rocker cover gasket , eccentric motor gasket and sensor seal. Found the eccentric sensor seal had potentially leaked oil into the sensor plug, so also replaced that. As to if it cured it, I wont be on the road until April 1st , so cant confirm it.

colb · Post by **colb** » Sat Feb 27, 2021 6:09 pm

Possible cam cover gasket is leaking and its finding its way onto the exhaust and burning off, looks like someone has been in there before judging by the red gasket sealant they used all around the cover. Gasket sealant is not required on these gaskets except for the front and back of the cover where there are half moon shapes where the gasket changes direction. BMW advise applying sealant around the half moons and between the vanos at the front no where else, the ribbed surface of the gasket should provide the required seal with the retaining bolts torqued up. I use Blue Hylomar gasket sealant on this job and have never had a replacement leak.
The oil looks higher up than the gasket so you need to take the covers off and have a look to see if there is anything leaking topside before pulling it all apart.

Jl-c · Post by **Jl-c** » Sat Feb 27, 2021 6:27 pm

Take the engine cover off, a few Dzeus fasteners and take a look if they spilled oil under the cover onto the top of the engine ?

GTwice · Post by **GTwice** » Sat Feb 27, 2021 7:13 pm

colb wrote: ↑Sat Feb 27, 2021 6:09 pm Possible cam cover gasket is leaking and its finding its way onto the exhaust and burning off, looks like someone has been in there before judging by the red gasket sealant they used all around the cover. Gasket sealant is not required on these gaskets except for the front and back of the cover where there are half moon shapes where the gasket changes direction. BMW advise applying sealant around the half moons and between the vanos at the front no where else, the ribbed surface of the gasket should provide the required seal with the retaining bolts torqued up. I use Blue Hylomar gasket sealant on this job and have never had a replacement leak.
The oil looks higher up than the gasket so you need to take the covers off and have a look to see if there is anything leaking topside before pulling it all apart.

It's not a sealant, the VCG for pre-modernized N52 (silver top, with magnesium valve cover) is exactly that colour.

GJ1 · Post by **GJ1** » Sat Feb 27, 2021 9:30 pm

Thank you for all the comments. Sounds like first step is to remove the engine cover.

What tool do I need specifically? Apologies, a complete novice!

GTwice · Post by **GTwice** » Sun Feb 28, 2021 9:33 am

It's just four 10mm bolts, basic ratchet will do.

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