The oil pressure in my W140 300SE pumps up immediately to the 3 and never drops below, even at operating temp and idle. None of the other benzes I have had have ever done this. Is this something wrong or normal? Most of them hovered between 1 and 2 at idle and operating temp.

Sounds like a defective sending unit. ON a "hot" M104 engine at idle w/A-C on normal pressure should be around 1 (about 15psi).

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Mine went "bad" on my 300E about a month ago...the needle would peg at the "3" position and remain there until I shut off the ignition. In fact, this would occur when I would first turn the key in the ignition...and not start the car!

I replaced the sender ($70 at FastLane and a five-minute install) and that corrected the problem.

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2009 ML350 (106K) - Family vehicle
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