TozoM8

I bought my CTT over a month ago with a cracked coolant reservoir. $75 later it was fixed and runs great just a hair under the 180 mark. This past weekend I got stuck in traffic and noticed that it went to the 0 on the 180. The AC wasn't cold either. Turning it off did not make a difference. It was constantly moving between 180 and ~195. Once the traffic cleared and hit 75mph the temp went to 180. Next day on the the way home after 30 min driving with 75mph it started to climb again to ~195. Another 30 min and it went down to 180 and stayed there for the rest of the trip. Ive had a couple German cars before and most had overheating issues, but never seen one like this. Anyone else experienced this?

Orantes

You may have air in your system. You may need to mechanically bleed the system...or your water pump maybe on the way out.

Orantes

I should add that it is not uncommon for trapped air pockets to occur in the Cayenne.

Budget M3

Sticky thermostat is also a likely culprit...

bigbuzuki

The temperature fluctuation you describe is normal.

As long as your needle stays out of the red it will be fine.

mudman2

+1 normal

TozoM8

Thanks for the replies. I will clean the radiators, replace the thermostat, water pump and the serpentine belt this weekend. I am driving from Chicago to Colorado in 3 weeks. I can't risk it with a sticky thermostat.

holgerericsson

Anothe culprit could be the radiator fans. I had the same problem and the mechanic found the fans were not turning on at the correct temperature. Replaced both fans. Themostats are cheap but take a lot of labor unless you do work youreself.

VIPNiSS

Is this normal then? I'm having an issue where highway it stays at 180 but stop and go traffic it hits 190-200 and back down. Fluctuates back and forth

alex911s

that's normal....

VIPNiSS

what is puzzling me is some other Cayenne owners dont have the issue.

mjr_cayenne04

Your temp fluctuation is normal. Mine hovers at 180, and ticks up in traffic. Also, replacing the thermostat is involves a ton of work - not your typical "follow-the-top-radiator-hose" to the thermostat housing. With regard to the waterpump, what typical fails there are the bearings, and unless you are hearing a bearing noise - this is quite noticeable - I wouldn't bother changing the waterpump just yet. If you decide to change out the thermostat, and the plastic coolant pipes haven't been changed, you will need to do that + the starter (since you are there and it is buried underneath the coolant pipes anyway). Plenty of topics covering the whole procedure on this board.

Ajna Autowerks

Hi there ,
I have a 2004 S model that I picked up a couple of years ago , I absolutely love it !! but it will overheat intermittently , the coolant pipes were replaced by a dealer in 2006 and since I have replaced the water pump , thermostat etc because it split a reservoir and although at the time I didn't know it was a common problem I figured I would eliminate all cooling issues hahaha ahhh
This is what happens.
Cooling system , filled with the heater on full and i run it until its warm , I shut it down and let it cool , top off the system and it runs great , the temp gauge stays right in the middle but if I run the climate control set to automatic , say 74 it will eventually heat up to 3/4 or more and dump the reservoir , it could be a day or a week later and I restart the process when cool , the only fix has been to check the reservoir and run the heater until hot each time I start it but it's driving me crazy with it not being right plus it has stranded me a couple times now.
Is there something im missing ? I have even tried to draw a vacuum on the system before topping it off
No codes , no low coolant light etc and the rest of the vehicle is 99% , and i say 99% because the only other issue is a bilateral valve cover leak but its more of a weep , could there be a vacuum issue that is causing the engine to lean out and overheat from that ?
Any suggestions would be awesome
Thanks
Michael

Jeroen Pipelers

I don't think these fluctuations are normal. I have two Cayenne S's one i have checked and it already has the alu coolant pipes, which is always on the middle mark. The other one goes to 200 when ac is off when ac is on stays on 185. This one i haven't yet had the intake off to see if it has the alu pipes. I also noticed that the coolant i add comes dripping out immediately so i have almost no doubt i'll have to buy them alus.

Anyway, i don't think it should go past the middle temp mark ever. If it does something is wrong imho.

DavieGravy

This is totally normal. Mine does this, but never goes past 210. Even going up an extremely steep incline in the utah desert during the summer it wasn't a problem. Most cars have 210 as their gauge center point, not 180.