I'm driving a Mercedes-Benz E 350 and after driving for about 5km and switching off the engine, the car smells like oil and smoke coming from underneath the car. What can it be

SOURCE: car stalls, oil light comes on, smoke from under hood

sound like the overheating of the engine did some internal damage. ethier an intake or head gasket or maybe even a warped or cracked head. worse case senero would be a cracked block. check the oil see if it looks milky like a grey sludge. most likely it is a head gasket. have a leak down test preformed to confirm. the labor for the head gaskets is 9 hours for 1 or 11.5 for 2. I would replace both and have the mechanic check the heads and block for cracks while he has it apart.

SOURCE: switch to 4 wheel drive in Mercedes Benz GL450

You have permanent all wheel drive dude. The system is always ready to go. If you want to do some offroading, activate the "off road" button that looks like a vehicle climbing uphill on the lower, center dash panel. This will allow more slip for the traction control system and hold lower gears longer in the trans

SOURCE: Engine Oil Capacity

the 320 and 430 models of that year held 8.5 quarts or 8 liters with filter replacement

SOURCE: 1990 Porsche 911 Carrara 2 Targa. Slight smell of

that oil leak or another is dripping on to the exhaust manifold or exhaust pipe ,that is where it is coming from,,

SOURCE: OIL PRESSUE LOW

At some point, your engine is registering low oil pressure and warning you the oil pressure is insufficient to lubricate the engine properly.

How does the engine know this? What causes it? Excellent questions. The engine 'knows' this because there is one or more sensors that read the oil pressure all the time. The sensors report to the computer which reports to you. They could be faulty. On the other hand, there could be times when oil pressure IS low. Your oil pump may be mal-functioning. Normally, I would expect the oil pump to either do its job properly or NOT do it properly but not act intermittently. It may warrant being checked by a professional. Another reason for this condition could be the oil itself, though you report you just had it changed. Presumably, whom ever did the change put in the proper oil grade, service and weight, recommended by GM.

Another thought, is this warning seen by you immediately after you start the car? If yes, it is normal for oil to take a second or two to build the proper pressure, particularly in cold weather. Where I am at, it is cold. Oil doesn't like to move when it is cold (like me) so it takes a bit of time to get up pressure (like me).

If this continues, you may want to have this problem looked at by a professional, as I said.

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