Has anyone had this issue?

My 2011 Cayenne (6 cyl) with 70K miles now has the engine coolant temp fluctuating 25 degrees between 200 and 175. For the last 7 years it has always warmed up to 200 degrees and stayed there like a rock.

Now it will warm up to 200 standing still, but the temp drops as its driven up and down between the 170s and 190s. I took it into the Porsche dealer a week ago and they ran pressure tests code checks, etc. and found no issues but they did not drive the car (no charge).

Last weekend we went with a Porsche group for Porsche Heratige Days up the "Dragon" in N.C. The engine temp dropped into the 180s going up an insane mountain switchback highway.

So, I took it back to the dealer and they tested it again and saw the temp drop. Verdict: no idea why it's doing it, but don't worry it's not overheating, (No charge and I got a free loaner every time).

I'd like to know if anyone else has had fluctuations in engine temp as well and how was it addressed. The dealer said they didn't want to throw parts at it and felt there was no harm driving. I'm not convinced.

Obvious culprits might be the thermostat or sensor, but the dealer said they received no error codes pointing to them. I appreciate not throwing parts at it as a thermostat replacement is expensive.

Any experience?

Thanks.

 

I had the same problem. Could easily drop from 90'C to 70'C while driving. Always went back to 90'C whenever I stopped on red light, in a trafic jam etc.

Changed the thermostat and the problem went away. Failing thermostat (to same point) will not give you any codes.

 

Hello,

I'm experiencing the same issue you had at the time of this post. I'm curious to know if you ever resolved this issue and what did you do.

Thank you