Island_Moose

Does anyone know conclusively where the ambient/outdoor air temp sensor is on an E63 W211? Mine has started reading double the actual temp and fluctuating wildly.

tw2

Sorry I don't know for sure for the E63 but most models have it behind the mesh inserts of the front bumper. All my previous Benz have had it roughly same place, right lower next to fog light.

Island_Moose

Solved!

The ambient air temp sensor is supposed to sit in a hole in the left side fog light grill. It clicks into a tube and the nose of it actually pokes out into the oncoming air.

Mine had fallen out, probably from scrubbing. I removed the 3 screws on the grill from the front, put the sensor back in and taped it securely. Reinstalled the grill. All fixed.

Random temps resulted from sensor falling out and sitting inside the air dam/engine bay.

tw2

Even in the correct location, just sitting in traffic the temp can slowly increase. I bought a new one with my last order. I suspect they slowly go out of spec as the resistance changes over the years.

Island_Moose

Do you recall the part number?

tw2

Sure 0075421318 I got it from pelican parts. I just picked up the Febi one for $12. $10 less than the genuine one and possibly the exact same part.
http://www.pelicanparts.com/cgi-bin/...ion=0075421318