A/C Air Smelling Burned Diesel - PeachParts Mercedes-Benz Forum

Diseasel300 · #11 11-09-2016, 10:14 PM

Quote:

Originally Posted by nyko46

It is more exactly like a smell of old lubricant oil heated by the hot engine block. Like I mentioned in another reply, my old 300 SD has a lot of blow back from an old engine and this blow back have a typical smell of burned oil.
When I stop on traffic lights with my A/C system running in ventilation only I get this typical smell inside the cabin. It is not as a smell of exhaust system but as a smell of heated lube oil.

Now we're getting somewhere. The smell of burnt oil is different from the smell of exhaust. It's entirely possible you have an oil leak somewhere and you're smelling the hot oil on the block. Would be worth your time to go peeking under and around the engine with a strong flashlight and see if you've got some oil leaking somewhere. Under-hood oil leaks that get hot enough WILL cause the smell to come in through the fresh-air intake since it's right there at the hood.