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Amorphic
12-03-2009, 07:40 PM
So for the last few weeks ive noticed my car is taking a long time to reach temperature. The coolant temp needle will get close to center and then it wil drop off almost all the way back to cold.

Is this a sign of a bad coolant temp sensor or is the thermostat on its way out? It takes over 20 mins for the needle to get to the center of the gauge.

Thanks guys.

spooledberries
12-03-2009, 07:43 PM
Do you have heat in the car?

Amorphic
12-03-2009, 07:44 PM
Do you have heat in the car?

yes. heater blows nice and hot. Ive been having a weird smell come into the cabin earlier and i was thinking i might have a leak in the heater core but ive run it through a few of my mechanic friends and they say it doesnt smell like coolant. might be some other issue or something else i havent figured out yet.

STGIIIs4
12-03-2009, 07:45 PM
Mine does the same thing...it will reach the center then drop all most all the way back down...then up again. Tryed to vag it for a fault but my computer shit out. But it does works properly at highway speeds. Audis....

spooledberries
12-03-2009, 07:48 PM
I would start with a coolant temp sensor. If it was your T-stat you wouldn't have heat or you would be over heating real fast

Amorphic
12-03-2009, 07:50 PM
I would start with a coolant temp sensor. If it was your T-stat you wouldn't have heat or you would be over heating real fast

perfect, thanks. i will throw a new one on and see if it fixes the issue.

collins
12-03-2009, 08:27 PM
mine was doing the same thing, then my oil temp stopped moving completely. just replaced my thermostat today and it fixed everything.

GrnAudiA4
12-04-2009, 08:49 AM
O.k...so if there is no heat but the needle takes a while to get to the center would that be a thermostat issue or is it the coolant temperature sensor?? I am having this issue with my A4 doing this same thing...I am getting very little heat...

sageleo
12-04-2009, 10:51 AM
I have heat, at least enough to melt snow/ice off of my windshield, but my gauge is doing the same. I probably should start with the sensor? How difficult/costly is it to replace the T-stat?

Amorphic
12-04-2009, 10:58 AM
I have heat, at least enough to melt snow/ice off of my windshield, but my gauge is doing the same. I probably should start with the sensor? How difficult/costly is it to replace the T-stat?

tstat and coolant temp sensor are not hard parts to change. If i do my tstat im going to be doing my belts and tensioners etc since its close to that time anyways. I think i'll end up doing everything just for piece of mind.

VirginiaBeachA4
12-04-2009, 11:05 AM
i have replaced my coolant temp sensor and my needle will stay at cold all the time until i stop and let the car idle, itll go up. but at the same time, i do have heat. i bought a new thermostat and im going to be changing it out. luckly, i have a 99.5 a4 so i do not have an internal water pump and will be easier to change my tstat.

Boognish
12-04-2009, 12:08 PM
Im having a similar issue, my thermo gauge and oil temp sensor will only go up one quarter, sometimes it won't go up at all, I cant tell if I get heat because my HVAC is stuck on the off button (eventually need a new one), not sure if its the thermostat/coolant sensor or the gauge cluster is faulty, (since my gas gauge will read correct and randomnly drop to empty, and back up),

collins
12-04-2009, 12:43 PM
t-stat took me about 25 minutes total. taking the throttle body off, draining the coolant, and getting the thermostat out, and everything back together. its really easy

VirginiaBeachA4
12-04-2009, 01:29 PM
t-stat took me about 25 minutes total. taking the throttle body off, draining the coolant, and getting the thermostat out, and everything back together. its really easy

is there a diy or can you sum up what i need to get to my tstat?

collins
12-04-2009, 01:43 PM
http://www.ray-cuthbert.com/audi/232/2009_10_08
that was the best guide i could find

collins
12-04-2009, 01:44 PM
and you dont have to take the bumper off to replace it. just the throttle body, the support under the intake manifold and the intake manifold hose.

bw86
12-04-2009, 03:22 PM
My temp gauge did the same exact thing. It would get to the middle then drop to 0 then slowly go back to normal.

I got the CTS from ECS for like $16 and installed in in 5min. Solved it right away.

2001A4QUATTRO
12-04-2009, 07:17 PM
The problem he is describing is a bad (stuck open) thermostat. It would not be a bad idea to replace the temp sensor as it is cheap. Only a thermostat will fix that. GL

VirginiaBeachA4
12-04-2009, 07:39 PM
http://www.ray-cuthbert.com/audi/232/2009_10_08
that was the best guide i could find

i have an aeb motor not awm.

bw86
12-05-2009, 08:02 AM
The problem he is describing is a bad (stuck open) thermostat. It would not be a bad idea to replace the temp sensor as it is cheap. Only a thermostat will fix that. GL

I've only replaced thermostats when I had no heat - he has heat.

mkturbo3
12-05-2009, 05:57 PM
i have an awm and have been having similar problems but mines never reaches 12oclock only at idle and once i start driving it will get colder to about 10oclock. just replaced the cooland temp sensor today didnt fix the problem but car felt alot better and came back to life. ill be doing the thermostat next. hope this helps