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I have a mk3 CL and was a little concerned when out and about tonight. I have always been paranoid with running temps of my car being too high but tonight was another matter!

My car usually runs at a little over 70 in 'normal driving' and 80 on the motorway. When standing the fan kicks in at just over 90. Which is ok.

Tonight when i went out the car was running a little under 70 in 'normal' driving and just over 70 on the motorway. When i was parked and left the engine running it wouldnt reach 90 for fan to kick in.... instead it went to just over 80 and dropped to 70 with no fan??? Any ideas?

What does other CL's run at??

Cheers!

Could be yours has developed similar problem to what mine had, but not as pronounced --- a stuck thermostat, and luckily, it's stuck "open". That is, the water's flowing through the radiator even when it doesn't need to be (rather than the opposite, much worse situation, where it doesn't flow through the radiator ever, and just loops back to the engine with very little cooling going on)

i hardly ever saw over 80c in summer, usually just a bit over 70. in winter i'd struggle to keep it out of the "COLD" zone (that thick white vertical line bit that goes downwards from about 50-60 degrees), particularly if i did any kind of speed (over 35-40mph! on freezing cold nights coming back from bar work, when outside air was rushing toward double negatives, i'd do the entire trip in 2nd, little faster than a scooter, as changing up or accelerating meant both I and the engine began to grow icicles)

after replacing the thermostat, its sitting at a healthier 75-90 range depending on outside air and how it's driven. havent any summer figures for that really yet though, as i replaced the offending article last winter and haven't driven it in the sunshine since... but i know i still had to work to get the fan to kick in. Not like before, where it was a good ten minutes of sitting it at 3000rpm in neutral with still air*, but even with a working thermo it's not rushed to overheat.

*this was however when i was trying to keep my bod warm on a winter's trip, and wanted to see if i could actually get the fan to activate or not...

Replace your Black temp sender, mate.

black temp sensor? think itll do the job?

thats the one that goes to the temperature guage isnt it?
(i was going to add something about the guage possibly being dicky, but it was late..)

i have a spare set of clocks too so would it be worth swapping the temp/fuel gauges over???

I'm very sure it's your black temp sender at fault, the way you desribe the gauge reading too low and the fan coming on too low.

It's located below the distributor cap, in the thermostat housing. You'll see a blue one and a black one. You need to replace the black one. Very easy to replace as well.

My GT runs at about 75-80 maximum.

I got fed up of the fan not coming on when it was supposed to, and have wired a relayed switch into the fan circuit, so I can activate it manually. I switch it on when in traffic for any length of time, and the temperature has never risen above 80deg. I, like you, am paranoid about temperature, ever since I had the car to over 110deg after the supposedly 'new' temperature sender failed after 3 days (damn VAG!).

fixed the problem

thought i would take a look at the black temp sender yesterday. took off the clip and cleaned the contacts now its all hunky dorey!! cheers for the help