First off I own a 2001 A4 1.8T.

I was driving home from work and after about 10min of driving my car overheated on the freeway. I was able to get it home but I'm not quite sure what the problem is. It will heat up extremely quickly when driving it (it would overheat in ~1/2mi if I drove it that long) but when idling it can maintain a temperature that puts the needle at about 2/3 to 3/4 of the way up.

- My coolant level is fine and the coolant itself appears to be clean and free of any oil
- My heater blows hot air and the top radiator hose is hot
- It worked just fine on my way to work 8 hours earlier

I suspect it's the water pump. I think that only a coolant flow issue would cause it to overheat that quickly. I'm thinking about buying this kit and having a mechanic install it. I figure if I'm going to pay them to tear the whole front end off to install the water pump I'd be foolish to not do the belts as well.

I'm looking for any insight\advice before doing this, as I know it's going to cost me quite a bit of money. Any help is appreciated.

 

Have to take a stab/guess at this...but it could be water pump: plugged radiator; WEAK bottom radiator hose that could be collapsing at higher RPMs;another possibility is a blown or leaking head gasket. A cracked head/block will also cause a vehicle to overheat when operated at higher rpm, the crack doesn't expand until temperature is excessive, but then you'd see steam coming out of your exhaust; fan clutch, blockage of exhaust; and we could go on....

Your temp gauge should never go ABOVE the middle....it should sit there happily....if it overheats in 10 minutes, it could also say that it could be your thermostat not opening at all....but then it should keep overheating even when at idle....but when you say it's at 2/3 idling thats also odd....your water pump idea might be the best way to go. I'd do some more testing before throwing money at it...

Start it in the morning after complete cool down and let it idle and see what happens? How fast does it warm up; look for steam out of the exhaust (normal when cold-should go away when at operating temp); where does the temp gauge sit when it's warmed up; does it fluctuate? While watching it, if the temp starts to go above the middle, see if your clutch fan is running, look at the bottom radiator hose and see if it feels like it's the same temp as the top one-don't burn yourself though...