Both radiator fans staying on after car is turned off.

[crazylegs]

About 9 months ago I had a CEL pop up because of the thermostat. The cars operating temperature was at about 192 instead of 190. Had the thermostat replaced and when I drove home from the mechanic, the large and smaller radiator fan turned on after turning the car off. They stayed on for 15 seconds and then turned off. Winter hit me and the temperatures dropped and this stopped happening. Now its getting warmer again and the radiators will do this for no longer than 15 seconds. I went back to the mechanic today to have it all checked out. He showed me a technical bulletin, just curious if anyone else has seen this. He ran all sorts of tests on the car and it was not throwing any codes and had no issues at all.

http://imgur.com/a/HMJJX

Car is a 2008 FSI GTI, thermostat was changed at 89k miles. Car is currently at 102k miles, APR Stage 1 with a neuspeed intake, noise pipe delete, no other engine mods.

 

[larcic]

how are you checking your temps? from what i've seen temps can range from 165-215 in torque app and the needle will stay dead at 190. no cel. its totally normal for your car to go over 200 or over 210 when standing still at a light on a hot day(needle will read 190 on the dot still). the boiling point of g13 is much higher than water. its also normal for your fans to stay on when you turn the car off. mine come on every time on a hot days unless i let it idle for 30-60s before turning it off. these thermostats normallly fail the opposite way(the car takes too long to warm up or doesnt warm up at all). what cel did you get? my company is blocking the picture so I can't see it....if you are looking at the dash gauge and its above 190 you are overheating more than you think...alot more

 

[crazylegs]

I forgot what the cel was, I believe the thermostat was slightly too open or not open enough? But the needle was one dash past 190 and then the CEL popped on, he replaced the thermostat and the CEL went away, but thats when the radiator issue occurred.

 

[larcic]

you need to check ur temps via vagcom or obd2 app...if its sitting above 190 its wayy higher than you think. your issue could be your temperature sensor since the thermostat was recently replaced. it would also really help to know what the cel was...was it cooling system performance??

 

[larcic]

oh never mind, i just re-read your post haha the only issue you are having is fans turning on on warmer days??? thats normal...just wait 60s before turning your car off and they wont turn on...

 

[snobrdrdan]

Yup, normal for the fans to stay on for a little while to cool the engine down.

If they stayed on for like 15 minutes, then you might have a problem lol

 

[GTI's]

Normal for it to run after engine shutdown for up to 15mins to cool engine down in usually warm weather.

 

[A41.8QTM]

Do they run on high and sound like a jet getting ready to take off? I had that issue last summer and it was the thermostat and/or water pump. Not sure because I just had them both replaced along with timing belt service. If the fans run for anything more than 15-30sec after turning the engine off then something is wrong. Even then, it shouldn't be a regular occurrence unless you drive in stop and go traffic during extreme heat. 90+ degrees and sitting in traffic might cause the fans to run a bit but otherwise they shouldn't once you turn the engine off.

 

[larcic]

not true...any stop and go traffic over 80 degrees ambient makes them turn on for me when the car turns off unless i wait at least 30s before turning the car off. they only turn on for 15s though. and my waterpump and thermostat are new. if you just look online its perfectly normal for them to turn on...

 

[A41.8QTM]

Maybe normal for you. I have the same 2008 FSI as the OP and in 90k miles over 8 years with temps commonly 90+ in summer I never had the fans run hard or long after turning the car off until the water pump started to go bad. Bottom line - your car should not be over heating, even in stop and go traffic, if the cooling system is working properly.