I have a problem with an OM603 wagon. The oil pressure pegs at 3 at startup, then it can suddenly drop to 0 on driving. Then it may creep up again to 2 or 3. I do see oil dancing out of the valve cover if I remove the oil cap. However, I don't have a chance to do it when it was showing 0 on the gauge. I suspect the low oil pressure may be real as my newly installed turbo seems to be damaged. I changed out the oil pressure sender in the oil filter housing but the problem remains. My next step is to change out the oil pressure gauge on the dash. What could be wrong?

1) Oil pump in the sump is slipping?
2) Blockage in oil passage?

Any insights are welcome.

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Not MBZ nor A/C trained professional but a die-hard DIY and green engineer. Use the info at your own peril. Picked up 2 Infractions because of disagreements. NOW reversed.

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