2.0 tfsi temp gauge low reading....

[yorksphil]

Hi, folks.... first post looking for a bit of advice, so go easy with me....

I have an A3 2.0 tfsi (bwa engine) and the temp gauge is saying coolant is running about 70 degrees when on the move, but does
climb back up to 90 when stood....
once i'm up to speed again it will drop back to 70 (ish).
temp gauge is reading correctly, as i have looked with vcds and an infra red temp reader and all say the same within a degree or so. Are there 2 temp senders or only 1 ?
i have replaced the temp sender unit (green top/ 4 pin)and it is still reading the same as before, confirmed with vcds and infra red.
so i am hazarding a guess at saying thermostat is stuck open...
Vcds did say on measuring blocks that stat was 100%, as i'm new to these engines, i don't know if the stat is electrically operated or not....
Or am i looking at a measurement that does not mean anything to this engine?
If anyone has any ideas on this i would be grateful, as i have had a good hunt for info, but can't find anything conclusive...
Many thanks, Phil.

 

[S3_Jacko]

I can't give you a lot of help here mate...but i'm sure if the stat if stuck open then your fan will be on constant?

 

[yorksphil]

I would think if stat is stuck open allowing full flow then it will be underheating, not requiring fan.
As opposed to overheating and needing fan to cool if flow was restricted....
Unless i'm missing the obvious .....
I shall wait to be shot down in flames!!
then get my coat..........
Thanks, Phil.

 

[JohnE]

Agree - stat jammed open seems likely. I had this on a 1.8 petrol passat once with exactly the same symptoms. New stat cured it but I had to have two goes at it because they sold me the wrong one first time.

 

[Lewis583]

Had the exact same on my 20T (also a BWA). Replaced the stat which sorted it. The stat that was fitted to mine wasn't an electric thermostat and came complete with the housing, because you are unable to dismantle it.

Not a particularly nice job as it's a bit fiddly.

 

[yorksphil]

Cheers, Lewis and John.... I was thinking stat, but wondered about the electrically controlled stat as vcds was giving an engine outlet temp and radiator outlet temp... guess Lewis has cleared that one up for me!

cheers.

 

[S3Alex]

This was one of the many problems found on my car.

Thermostat stuck open and the engine running at 70C.

 

[yorksphil]

Cheers, Alex....... i reckon that confirms it!
guess what ill be doing shortly...?

:icon_thumright:

 

[S3Alex]

Cheers, Alex....... i reckon that confirms it!
guess what ill be doing shortly...?

:icon_thumright:

Maybe a trip to a tuner near you?

 

[S3_Jacko]

I would think if stat is stuck open allowing full flow then it will be underheating, not requiring fan.
As opposed to overheating and needing fan to cool if flow was restricted....
Unless i'm missing the obvious .....
I shall wait to be shot down in flames!!
then get my coat..........
Thanks, Phil.

No no, your right mate... stat jammed closed will be doing this... sounds as if it might be the stat.. only 1 way to find out

 

[yorksphil]

Hmm... possibly possibly, could do with a bit more grunt (previous toy an RS6 )

 

[OVRA3]

To agree with all the above just had this twice in a year! Once stuck open next stuck shut :-(

 

[Lewis583]

As luck would have it, I still have my old stat in my bedroom form a couple years ago. I don't know why I've still got it either

The stat housing

The actual thermostat

The part number (06F 121 111 F)

Note: yours may be different.

When ordering the part give your reg/chassis number to them and they will sort which one you need. Not sure if an aftermarket item is available, but even if there is I would go with OEM. Best places to buy from are TPS or Audi main dealer.

 

[LEE69]

Can tell the colder weather is coming, not holding temp when moving is stat.

 

[S3Alex]

Hmm... possibly possibly, could do with a bit more grunt (previous toy an RS6 )

You know what to do....and what a slippery slope it is....

 

[yorksphil]

As luck would have it, I still have my old stat in my bedroom form a couple years ago. I don't know why I've still got it either

The stat housing

The actual thermostat

The part number (06F 121 111 F)

Note: yours may be different.

When ordering the part give your reg/chassis number to them and they will sort which one you need. Not sure if an aftermarket item is available, but even if there is I would go with OEM. Best places to buy from are TPS or Audi main dealer.

Will stay with oem parts for sure! cheers for info....:icon_thumright:

 

[yorksphil]

Thanks for the replies folks!

You know what to do....and what a slippery slope it is....

indeed, and a very steep slope at times!!

 

[S3Alex]

Thanks for the replies folks!



indeed, and a very steep slope at times!!

I know...just not sure what part of the slope I'm on at the moment!

 

[yorksphil]

stat in and running at 90 degrees, just in time for the coolish weather...
Cheers for the advice folks....

next problem, new thread.... boo hiss

 

[TurboMan[slo]]

had a real big problem with temp too low on a golf gti v dsg 2.0 tfsi. changed the main thermostat and the problem persisted.


turns out that the car has 3 thermostats.

one "main" one, one for turbo, and one for transmission (dont know if manual has one)


now the car gets to 90c degrees in 8 mins and stays there no matter what.


Home Page Search Transmission Thermostat ES#382259 Transmission Cooler Thermostat - 4E0121113

[h=1]Transmission Cooler Thermostat[/h]

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In line thermostat leading to the trans fluid cooler
In order for your transmission fluid to warm itself to operating temperature under extreme cold conditions this thermostat may remain closed until coolant reaches a certain temperature. This thermostat is located in the main line leading to the transmission oil cooler assembly.

 

[s5joe]

This is a pig of a job