Ive been fixing the nickle and dime stuff on my 1990 300D 2.5. I broke the vacuum nipple off the shut-off valve somehow and while i was replacing it i realized i didnt know what the connector was that i had to unplug to get to the back bolt. That connector appears to be the source of an oil leak. Is it part of the TPS system? Does it come off relatively easy?

The control rod sensor connector is inboard of the shutoff actuator. The IP has to come apart to replace the connector seal. Clean and dry the area then smear some RTV. Can’t hurt.

Sixto
98 E320s sedan and wagon
02 C320 wagon

Its not that big of a leak. I'll take up your advice and rtv it up. Thanks!

If it's the rack position sensor (black plug on top of the IP) it shouldn't be anymore than a sweat at worst. If it's pooling enough oil to actually drip down the sides of the IP, check your blow-by conditions and try snugging the threaded collar that holds the connector in place.

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