Temp reading

[1animal1]

Hola!! just playing around on the way to work this morning and decided to check the inlet temps.... i think this is option 49 on the aircon unit....

anyway, sat mostly at 78 C but went down to 69 C whilst coasting down a long hill, is this normal? my temp gauge also went to about 80 C whilst this was happening...whats the diagnosis chaps?

 

[Imteyaz]

I could be wrong here (somebody please correct me if I am) but using '49' function on the aircon screen tells you the temperature of the coolant that the ECU will see, not inlet temperature.

I had the same issue, temp would drop on long journey but steadily rise when stuck in traffic. I changed the thermostat (and dipstick tube as it shattered whilst trying to access the thermostat) and checked again to see that the temp stayed at 90degC once warm.

Thermostat from a stealer is about £12, dipstick tube about £3 and the grazed knuckles you get from doing the job are free!

 

[Westy]

yeah if your temp guage on the dash is showing the same as your aircon reading then you'll need a new thermostat.

 

[FazS3]

Thermostat fella

 

[Prawn]

it's a very typical VAG problem, that the thermostat starts to stick open. it's not doing any massive harm, although it'll take longer to warm up, and won't usually reach 90 on a run. it'll also probably get progressively worse.

My car runs fine at 90 in summer, but in the cooler winter months, it rarely gets above 70 degrees, which is ****** annoying!

New stat will cure it

 

[HTC]

Theory-o-etic-cally-ish (spelling ) an engine not running at it's designed temperature might cause raised engine wear.

I concur, it's a thermostati-cally-isk problem.

 

[1animal1]

cheers guys, i thought as much but wanted clarification..... the temp display isnt showing the same as the aircon yet but assume its best to change

will do a search for the guides to replace......

 

[V.I.P_UAE]

Yeah as everyone explained, its the thermostat, mine was the same last week, I was on the motorway and it went all the right down to register nearly nothing. Changed the thermostat this week and it is now a rock solid 90deg always once up to operating temperature.