DaveInSaltLake

I futzed around today and replaced both the F76 and G62 temperature sensors. Autohausaz.com had both in stock for my 92 100 CS.

If I can believe the onboard computer, this R&R perked my gas mileage right back to where it should be. I noticed a significant drop in mileage (from about 24 mpg to about 14 mpg) when the ambient air temp dropped to freezing or below.

I'll update this message again after I drive it for a week or two and see if the mileage problem is truly fixed.

Handy tools for the job included a plumber's "basin wrench" to get the F76 loose and then tight again, a coat hangar hook to trigger the wire retainer on the electrical socket on the G62, and a 19 mm ratcheting box end wrench to loosen and tighten the G62.

Link to an earlier post about the diffences in function for the two sensors:<ul><li><a href="https://forums.audiworld.com/a6100/msgs/55532.phtml">https://forums.audiworld.com/a6100/msgs/55532.phtml</a</li></ul>

20VT90q

the engine temp is at. It uses this along with the maf, o2 sensor, etc. to determine how much fuel to dump into the cylinders. The F76 switch is only used for your instrument cluster coolant temp readout and for the a/c system(if engine is too warm it shuts the a/c off). Both are pretty easy to do and pretty cheap($55-70 total for both) at any online parts distributor.

DaveInSaltLake

studied the link in my original post very carefully. Nice recap.

20VT90q

;-) That and I replaced the G62 in the not so distant past...