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kilian tuning
September 26th, 2011, 09:41
It seems my coolant fan is running constantly, it starts running after starting the (cold) engine and keeps runnig untill the engine isnt running. The temp never exceeds the 90 degrees.
What can be the cause of that?
Dont think it will damage anything, except the coolant fan will be worn out sooner...
kismetcapitan
September 26th, 2011, 09:48
is your A/C on? I just drove the car around the neighborhood (to see if my suspension would settle...don't ask, I'm imagining things with my DRC circuit pressures...), and my fan came on. I switched the climate control to "ECON" and the fan turned off and I was no longer bothered by the whirring sound.
speedtrapped
September 26th, 2011, 11:11
Also it may be time for new green sensor....that's the coolant temp sensor. When they go fan will constantly run. vAG for code. Mine came up, replaced and no code anymore or running fan. Thankfully a cheap part on car.
ben916
September 26th, 2011, 18:28
Um, Wade had the same issue - turned out to be the Thermostat...
Hy Octane
September 26th, 2011, 18:43
Yep. Thermostat..
4everRS
September 26th, 2011, 18:47
Same thing happened to me. T-stat. Good thing it's so easy to get to!
SteveKen
September 26th, 2011, 18:56
. . . T-stat. Good thing it's so easy to get to!

lol.

When is your timing belt service due?

Cold starts in with winter will not be good for the internals if you leave it as-is.
Elevens
September 27th, 2011, 03:04
Not certain what the immediate problem is, but I doubt its a Thermostat issue. That would have nothing to do with the Fan starting immediately after a cold start up. I believe this was discussed in a past thread. Can't remember when or where. It wound up being a little more complicated than a shorted Coolant fan Switch. I'll attempt to find that thread........
ntrcptr
September 27th, 2011, 06:30
lol.

When is your timing belt service due?

Cold starts in with winter will not be good for the internals if you leave it as-is.

ditto... had recent similar problem. test it. go wOOOTTT! THEN sEE IF CAR overheats..
kilian tuning
September 27th, 2011, 13:55
Elevens :

Not certain what the immediate problem is, but I doubt its a Thermostat issue. That would have nothing to do with the Fan starting immediately after a cold start up. I believe this was discussed in a past thread. Can't remember when or where. It wound up being a little more complicated than a shorted Coolant fan Switch. I'll attempt to find that thread........

Thanks, im looking forward to see that tread.
Thanks to the rest who replied to my tread so far, as it is only my weekend car, im gonna check those things/possible solutions asap...:)
Hy Octane
September 27th, 2011, 18:32
Not certain what the immediate problem is, but I doubt its a Thermostat issue. That would have nothing to do with the Fan starting immediately after a cold start up. I believe this was discussed in a past thread. Can't remember when or where. It wound up being a little more complicated than a shorted Coolant fan Switch. I'll attempt to find that thread........

Well, dont bet on it. I had the same symptoms. Fan on hi immediately after start up until shut off. It was the thermostat.
Checked the G2 sensors but it was definately the t-stat.. I'd start there.
4everRS
September 27th, 2011, 19:21
ditto... had recent similar problem. test it. go wOOOTTT! THEN sEE IF CAR overheats..

Pretty much every tstat made now is what's known as a "failsafe" tstat. Meaning, when it fails, it fails in the open position. What Steve is saying, is that during very cold temps, if the tstat is open immidiatly after startup, it will be pumping coolant at very low temps through an engine trying to warm up. Not good for the motor at all.

Plus the OP said temp never exceeds 90'C. The temp guage in euro versions have the temps listed in the guage. Something the US shouldve had too.
Elevens
September 28th, 2011, 03:29
Well, dont bet on it. I had the same symptoms. Fan on hi immediately after start up until shut off. It was the thermostat.
Checked the G2 sensors but it was definately the t-stat.. I'd start there.

Thermostat is Strictly Mechanical, which opens and closes based on water temperature. No way it could cause an electric fan to start immediately upon cold start up. And besides to start at the Thermostat would be a huge undertaking since you would have to remove the whole front end just to gain access to It. Might as well do a complete timing belt-water pump job. I haven't been able to locate a past thread on the topic, but I am still looking.............................
Elevens
September 28th, 2011, 03:51
Found this past thread. It may not be exactly your situation but it is related. Check it.


http://www.rs6.com/showthread.php/22229-Revisiting-a-topic-After-Run-Fans?p=208372&highlight=#post208372
4everRS
September 28th, 2011, 04:21
The T-stat itself is mechanical as mentioned. As Hy Octane has said, I have had the same situation. Not sure if I understand why, maybe there's a sensor that detects coolant flow, and if the temp sensor is saying its too cold to have flow, emergency mode is tripped. I don't know for sure.

In my situation, I suddenly noticed the fan coming on as soon as I turned on the key. Didn't even have to start the engine. While driving the car the fans were always on and sounded like a jet. My coolant temp gauge in the cluster would not get past the first hash mark, or about 25% up the gauge. I did a t-belt service with Pat. Changed tstat, water pump, and the rest of the t-belt service. Fan problem suddenly gone.
Thermostat is Strictly Mechanical, which opens and closes based on water temperature. No way it could cause an electric fan to start immediately upon cold start up. And besides to start at the Thermostat would be a huge undertaking since you would have to remove the whole front end just to gain access to It. Might as well do a complete timing belt-water pump job. I haven't been able to locate a past thread on the topic, but I am still looking.............................
4everRS
September 28th, 2011, 04:25
For the record, you should start with the easiest, and cheapest potential fix first.
kilian tuning
September 28th, 2011, 18:03
it turns out to be the uh....:( econ switch...
SAF
September 28th, 2011, 18:35
LOL, the AC was running?
kilian tuning
September 28th, 2011, 18:43
uhh yyes.....:)
kismetcapitan
September 28th, 2011, 18:45
WIN!! I diagnosed the problem!!! :D :D :D
4everRS
September 28th, 2011, 20:21
it turns out to be the uh....:( econ switch...

LMAO. Thank a for at least having the kahunies to admit it. When the cooling fans are in emergency mode, it is much louder than the AC fan.

Haha, look al all our stupid posts! Nice job kisme, that what forums are for.
SAF
September 28th, 2011, 20:44
uhh yyes.....:)

Cheapest fix ever!