Wow! My car did the same thing yesterday. I had started an thread on this back in november. I put in a brand new OVP 2 months ago for same issue. Yesterday it rained ALL day. I get to my car to go home from work, and yup, check engine light is lit. Im just like WTF.

I inspected it when I got home, and it was soaked with rain water. apparently in one of the unions of the plastic "gutters" under the windscreen, water is allowed to drip, DIRECTLY above the OVP. I have it out now on the heat register in my house and will try it in the morning. When I put it back in, im going to zip tie it deep in the back, and not in the normal mount.

W124 6-cyl owners beware. Be sure your not getting a water leak in your electrical box behind the battery.

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93 300D 2.5 Turbo, Black/Palomino 273K
09 E350 Black/Black 41K