Hi everyone,

Got a TT about two weeks ago. Black roadster with a huge number of mods, mostly unidentified: unknown FMIC kit, unknown turbo, unknown software, borla custom exhaust and TP, unknown injectors, some strange injection system (looks like it injects something into air intake) e.t.c., turbo easily push 20-25psi ... When sold for the first time it was 180hp FWD; No any records other then carfax records.

Still working to figure out more about it. Drives well but there is an issue:

When idling or driving through the city, coolant temperature stays where i think it should be: middle on the cluster, on climate control (49C) shows 80-82C and (51C) shows 90C; when on highway and if it is colder then 60 degree (pretty much all the time now in MN) coolant temperature drops one notch on a cluster, at (49C) to 74-76C depending how cold is it outside and stays at 90C on (51C); I've replaced cool. temp. sensor. (the green one) - changed nothing;

Is this a normal behavior? Thermostat?

Couldn't find much about it on forum so far... What is the difference between (49C) and (51C) on a climate control - because (49C) temperature follows the reading on a cluster and (51C) stays at 90 always (once gained).

P.S.
(49C) and (51C) in brackets are the codes are used on climate control to pull the temperature readings.

 

i have a cooler thermostat in mine and mine does that. in other words mine is suppose to do it. not sure about urs. no issue unless your running hot. or if your heat don't work in the car.

 

Mine does the same thing. If the temperature drops below 70*F, the car will never reach the middle of the temp scale; it will always stay 1 notch below. When I turn on the heater the temp drops a little more and the air doesn't come out hot. Any ideas?

 

hm, not sure about air temperature but it seems mine is blowing hot, not as hot as my A4 though ... any ideas?

 

Okay so if anyone cares, the solution to my problem. The thermostat was shot and was not opening/closing properly. I used the doc at http://forums.audiworld.com/tt/msgs/1304805.phtml to fix the problem.

 

My TT does the same thing. It is usually one notch below the Middle when cruising normally and will only reach the Middle once Ive let it idle after running it for a while. I was told by one person that this is normal, any opinions?

 

AFAIK, it's not normal. The thermostat is not opening and closing at the right temperature. If you're having problems with the heater air coming out cold, I would recommend replacing the thermostat. I bought the thermostat from the dealership for $25 (I heard ECS had some problems with theirs), some G12 coolant, and the dip stick tube. It took about an hour total from start to finish. Also, I would recommend a tray beneath the car to catch the coolant which will pour out. Lastly, it's a pain to remove the bottom screw holding the thermostat housing, make sure you get a long extension.

 

Thanks ret, looks like I'll have to do the thermostat this weekend. I did the thermostat on my Passat and it was kind of a PITA to say the least. And you mentioned something about the dipstick tube, do I need a new one?

 

It was a bit of a pain. However, the website documents the entire process in great detail. While you're at the dealership, I would pick up the dipstick tube just in case. Mine broke in half as I was pulling it out. It's only a $6 part. Don't forget the thermostat o-ring.

 

time to do mine this weekend. Cold garage will be a piece of interference with process but hopefully ...