Had my car for about a week now and the temp gauge is acting very strange. When i start the car it is at "C" like it should be, then as the car warms,the gaugeseldom moves more than a centimeter. Every once in a while ill check it after ive been driving a while and it will be in the middle (where it should be) then ill look at it 2 min. later its all the way to "C" again. Im not too knowledgeable under the hood of thecar so i was wondering if anyone had any advice. Sticking therm., bad coolant temp. sensor,i dunno. Its a '04 A4 quattro 6mt with 53k miles... the car isrunning great so im not too sure what to thing, any advice is appreciated...

 

are you getting hot air into the cabin?? if not you could be overheating due to the thermostat being stuck which keeps the top of the radiator cold and the needle in the dash low

 

If you are getting heat......^^^^
Since it gets to the middle and jumps up and down sporadically, its most likely the coolant temp sensor, or a bad connection to it. Try cleaning the harness, if that doesn't do it, replace the sensor.

 

Is it ***** *** cold where you are? In summer mine will ride right down the middle no problem, or if I idle to long in winter, but once I start moving in negative temps yeah it will go down to the C again. As long as the air is still blowing hot your fine.

 

Hi, I've got a similar problem on my A4.
Can anybody tell me where the coolant temperature sender is on 1998 TDI ? . The Haynes manual diagram does not look anything like mine.
A picture would be even better. Thanks

 

ive been seeing alot of these posts lately, i had the same problem and turns out it was a bad thermostat, although i would suggest replacing the temp sensor since it is known to go. im pretty sure if the oil temp dosent go up then the thermostat is a def since the oil temp has its own sensor. if you have a v6 its about 3-600 to replace the thermostat since its behind the t-belt. so if you havent replaced that in a while you might as well go in and get that taken care of along with the thermostat, water pump and serpintine belt. aldo if youve been running the car like this for a while i suggest changing the plugs, when i pulle dmine out they were fouled from haveing the cylinder temp suddenly rise when i got on it. if you want to replace t yourself, good luck because its a B****. took me a combined total of 10 hours to replace it myself

 

I have been having the same exact problem in my 01 a4 1.8 sometimes the temp gauge stays cold when it obvious the engine is not that cold (i live in so cal) i have heard there was a recall for the thermostat... or that they sometimes stick... i plan to replace mine soon... hopefully that will do it.... if not i will lean towards the temp sensor.

 

TDi temp sensor location

[IMG]local://upfiles/12092/7090C928447F46DD8E37D13A60FA886B.jpg[/IMG]

 

thanks for the info... its been kina cold here for the last week temps between +1 and +21, but on my way home from work it was like 36 out and the gauge went up half way and stayed the whole drive home... so i think its just the unusually cold weather we've been having

 

even with very cold weather the gauge should be in the middle (besides that isn't cold. Saskatchewan with -40 is cold). Sounds like a bad thermostat.