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tmr931
11-28-2009, 08:09 AM
well ive noticed for a while that it takes my car a long time to warm up. Well last night was our coldest night so far (30F). I went to leave my buddys house. Started my car and let it warm up for about 10 mins. When I go to leave, I noticed the temp needle hasnt moved at all. It was another 5-10 mins into my drive until the car was up to normal operating temp. 20 minutes seems like too long, right? Im thinking I need to replace my thermostat. Or is that normal?

Also, my oil takes a long time to warm up as well. During short drives (15 minutes) the oil temp gauge doesnt even move. It really only moves when I get on the highway or am running at high rpms, and even then it only goes about 1/4 of the way up, at most (i forget the exact temp). Is that normal? Someone said it was due to bad oil, but im running fresh mobil 1 0w40.

The car runs fine during this warm up process. The idle drops like it should after about 30 seconds, etc etc. What do you all think?

One more thing, im sure its been covered and I will search, but feel free to comment on changing the thermostat. How hard is it? Where is it? etc?. Ive done plenty of t-stats and they have all been easy, but I have a feeling its going to be buried on my audi.

VirginiaBeachA4
11-28-2009, 10:02 AM
i need to do the same as i know my thermostat is stuck open and the water temp gauge never moves unless i have stopped for a while. supposably, we have a water to oil cooler and by having a thermostat stuck open keeps the oil temp pretty cool and there for not really having a "normal" reading of the oil temp gauge either. i have my thermostat, i just need to go get some g12 coolant. after reading some diy for a timing belt/water pump change, seems that the thermostat should be around the water pump, which is easily accessible by going under the car.

salz2135
11-28-2009, 10:03 AM
Coolant temperature issue: sounds like you're describing a thermostat that is wearing out or might be stuck in the open position. Coolant temperatures should reach at least 80 degrees celsius while driving. However, there could be other problems as well. You may have a problem with your coolant temperature sensor, or you could actually have an issue with the gauge on your instrument panel.

Regarding replacement of the thermostat: it will depend on what motor you have in your car.

"Bad oil" would not cause the second issue your describe. If anything, "bad oil" would make your temps increase too quickly. It's more likely, that you have a problem with your instrument panel gauge, or your temperature sender is faulty.

Upon further thought, the two issues might be related. If your thermostat is not functioning correctly and your coolant temps are too low, this may contribute to keeping your oil temperature low due to the water cooled oil cooling system.

Coopa
11-28-2009, 11:00 AM
Replacing wise, the thermostat is a breeze to replace. Get it in the air somehow so you can get underneath the engine. Belly pan comes off. Drain your coolant. On the drivers side of the engine there you'll see the thermostat housing body and a large coolant hose going to it. Unclamp the hose (there will be a little coolant left over to drain out) The body is held on by 2, 10mm bolts. They are somewhat difficult to get to if you have boxing gloves for hands like myself. A "micro ratchet" with a flexible extension will help greatly. T-stat housing comes off and thermostat and rubber o-ring will come out with it. Replace in reverse order. The only difficulty I had was purging all the air out of the system after I replaced the cooland and t-stat. Airlocks are such a silly problem. Be sure to purge all the air out of the system and you're good to go. [wrench]

salz2135
11-28-2009, 11:05 AM
He didn't even tell us what motor he has. Why are you assuming he has an AEB or ATW?

tmr931
11-28-2009, 05:00 PM
engine is ATW.

The wierd thing is, my car gets up to normal operating temperature, it just takes forever. And im pretty sure my oil and coolant temp issues are related, because when the car is up to temp, the oil warms up too.

oksk89
11-28-2009, 05:18 PM
I have this same exact 'problem.'

Takes forever for the coolant gauge to reach the middle, or near the middle. I have to drive about 10 minutes for it to start moving, or drive really hard.

As for the oil gauge, it moves only very little. I've never seen it past the 1/4 mark. The most it moves, I think, is one notch on the gauge.

Coopa
11-28-2009, 05:25 PM
He didn't even tell us what motor he has. Why are you assuming he has an AEB or ATW?

He's pretty frequent on here and I knew it was a 1.8t.

Good point though..the v6 is a different story.

As far as the oil temp and coolant temp issues goes, My temp gauge used to go up to half when the thermostat was on its last leg. Changed it out and it justs warms up 10x faster. My oil temp gauge is still doing the same as yours. Takes forever to warm up. Kinda wondering what the deal is..

salz2135
11-28-2009, 06:27 PM
He's pretty frequent on here and I knew it was a 1.8t.

Good point though..the v6 is a different story.

As far as the oil temp and coolant temp issues goes, My temp gauge used to go up to half when the thermostat was on its last leg. Changed it out and it justs warms up 10x faster. My oil temp gauge is still doing the same as yours. Takes forever to warm up. Kinda wondering what the deal is..

Yes a 2.8 will have a different procedure as you agree. However, the 1.8t procedure for replacing the thermostat is different for the AEB/ATW blocks and the AWM block. The difference is due to the external versus internal water pumps and corresponding thermostat housings.

My point was for the poster to state what motor we're talking about here, so that when someone searches for help and finds this post at a later date, he won't be misguided.

BlackLock_A4
11-28-2009, 07:24 PM
A little trick to our cars is you can check your coolant temp another way than by the needle on the dashboard. In the climate control, hold the recirculating button and press the "up" arrow for the vents. You should then see "1Q". Change it to "51Q" for coolant temperature by using the + and - buttons for the temperature. Normal operating temperature should be 90 (centigrade).
My needle does not work so I check up on this from time to time.

Just for fun, "27Q" is RPM... it's a fun distraction sometimes [:D].

Eric