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Does your m54 car smells like burnt oil all the time?

9.4K views 22 replies 12 participants last post by  Evane18  
#1 ·
Hello, I was just curious if anyone can relate to burnt oil smell from engine bay. I am experiencing this in my 2003 325i m54. There are no visible oil leaks on the engine. Smell is quite significant and sometimes goes into cabin. It probably has something to do with oil consumption which is present on my m54.

Is this normal on your m54 cars? Thanks
 
#7 ·
Any smell of burining oil indicates leaking oil reaches exhaust manifold, cats of exhaust pipes. pretty common leak is sweating valve cover gasket. some major leaks like oil pan or oil filter housing gasket contaminates engine but doesn't reach exhaust therefore doesnt burn. Valve gasket replace is less than 1 hour job.
 
#8 ·
Any smell of burining oil indicates leaking oil reaches exhaust manifold, cats of exhaust pipes. pretty common leak is sweating valve cover gasket. some major leaks like oil pan or oil filter housing gasket contaminates engine but doesn't reach exhaust therefore doesnt burn. Valve gasket replace is less than 1 hour job.
True i did my valve cover gasket in about 35-40 minutes but my gasket wasnt baked to the valve cover like ive read they can do which can make the job take longer because you can accidentally break the valve cover trying to get it off but if thats the case I read soaking the old gasket with engine degeaser or dawn dish soap to loosen it up

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#10 ·
You are describing a valve cover gasket that's leaking onto the exhaust.

The engine is raised on the front and tilted to the right (exhaust side) and the oil gets pumped to the top and it flows by gravity back to the oil pan to start the journey again. The oil flows to the back of the engine to the #6 cylinder area. There are drain holes at each cylinder, but any oil that misses the drain holes at the top (#1 cylinder) flows to the next and so on until the oil pools over #6 as it prepares to drain to the oil pan. If the valve cover gasket is a fail, oil will drip onto the exhaust manifold, typically at #4, #5, & #6, or down the back of the engine between the engine and the firewall. All of the stuff that the oil can drip onto is hot and the smell of burning oil is a common complaint. The oil can actually burn off and you do not observe wet oil but you might see the stains that result. Occasionally you can put a turn or two on the valve cover bolts if they have backed out, but replacing the gasket is the thing that smart money would do. When the gasket is replaced, there are 15 or 16 screws that hold the cover on. You must replace the rubber grommets on these screws else the dry rubber will give you leaks again. The valve cover gasket is a rectangular item then there are two gaskets that have the spark plug holes molded in, and the 15 or so grommets.
 
#12 ·
You are describing a valve cover gasket that's leaking onto the exhaust.

The engine is raised on the front and tilted to the right (exhaust side) and the oil gets pumped to the top and it flows by gravity back to the oil pan to start the journey again. The oil flows to the back of the engine to the #6 cylinder area. There are drain holes at each cylinder, but any oil that misses the drain holes at the top (#1 cylinder) flows to the next and so on until the oil pools over #6 as it prepares to drain to the oil pan. If the valve cover gasket is a fail, oil will drip onto the exhaust manifold, typically at #4, #5, & #6, or down the back of the engine between the engine and the firewall. All of the stuff that the oil can drip onto is hot and the smell of burning oil is a common complaint. The oil can actually burn off and you do not observe wet oil but you might see the stains that result. Occasionally you can put a turn or two on the valve cover bolts if they have backed out, but replacing the gasket is the thing that smart money would do. When the gasket is replaced, there are 15 or 16 screws that hold the cover on. You must replace the rubber grommets on these screws else the dry rubber will give you leaks again. The valve cover gasket is a rectangular item then there are two gaskets that have the spark plug holes molded in, and the 15 or so grommets.
Thanks for the explanation. I had the same problem a few years back. Replacing the valve cover gasket solved the problem.
 
#14 ·
Hello, I was just curious if anyone can relate to a burnt oil smell from the engine bay. I am experiencing this in my 2003 325i m54. There are no visible oil leaks on the engine. The smell is quite significant and sometimes goes into the cabin. It probably has something to do with oil consumption which is present on my m54.

Is this normal on your m54 cars? Thanks
How many miles are on the car?
Have you replaced the valve cover gasket or old filter housing gasket (OFHG)?
How old is your CCV system (original?)?
 
#23 ·
Hello, here’s a little update on the situation with burn oil smell.

As some forum members here suggested, I have inspected back of the engine and there was a huge leak from under valve cover which dripped on the exhaust which caused burnt oil smell. I have changed the valve cover gasket with all the rubber O rings and will see what differecne it makes after some kilometers.

Thank you for help :)