weird smell from engine bay

[mrrsharma@yahoo.com]

f15 N57 160K

Recently (starting last week) I’m getting a weird smell from the engine bay, can’t tell if it’s exhaust fumes or gear oil.

I checked the EGR and the intake and doesn’t look to be melted or leaking. EGR was replaced about 4 months back. Convoluted section look fine, no soot or cracks I can feel.

The smell is strong enough that if I get out of the car while it is running and leave the drivers door open and get in a minute later the fumes get into the cabin. But there is no smell if I keep the windows close and stay in.

I know the smell of leaking coolant, and the coolant tank looks good, no loss of fluid and I can hear the pressure release when opening the cap.

I checked for oil leaks around the valve cover and oil filter housing and it was fine.

Are problems with the differential common?

I don’t think it’s brake fluid cause I’d have a soft pedal. So it’s limited to a few things.

No codes, what are the top causes? Or drive till it tells me something?

[50iXman]

Is it a burnt smell?

[mrrsharma@yahoo.com]

Maybe a slight burning smell, can’t tell if it’s oil or gear oil or plastic. I think it is not as bad as it was…

[robbief00]

Make sure you check the valve cover gasket all the way in the back corner (passenger side). This is typically where a small leak pools up and drips onto the hot parts below causing a burning smell.

[tlow98]

Originally Posted by robbief00

Make sure you check the valve cover gasket all the way in the back corner (passenger side). This is typically where a small leak pools up and drips onto the hot parts below causing a burning smell.

What I’d recommend as well. Pretty typical. Smells acrid like plastic or oil burning. That’s bc it’s a little of both :-)

[XxBBVTMxX]

Check your PCV hose, it might be cracked and allowing vapors to escape.

[mrrsharma@yahoo.com]

I checked the pcv hose, no issue there, I feel like it’s more from the drivers side than the passanger side…

It comes and goes.

Plan to change out the front diff oil to see if it’s Low or burning something there.

[Clifton]

If it is on the driver side, that could point to melting intake via the EGR. Issue is documented in the current recall. I've seen others post returning issues even if the recall was performed.

Other items would be oil filter housing or oil spill from oil filter service.