98 A4 with 2.8. Temp gauge sometimes reads normal and others stays cold (does not move). Could this be the senor? I can see the senor, but how do you get to it? I have the blue one.

 

take the intake tube off all the way to the throttle body, its easy after that. Make sure to take the top off the overflow tank and let the air bleed out first or your going to loose a ton more coolant than you need to. You need the square sensor, it will probably be green when you do get it, but as long as its square your good. This sensor is worth replacing just as a maintenance thing, it causes a lot of problems.

 

cheap and easy most local autopart stores carry them prolly same as VW but more $$ got a green top to replace black one on mt 01 TT, exactly same as my 01 jetta 1.8T

 

Thanks Advance Auto had one. How do you get the part on the throttle body off? My manual is not much help. I see a bolt on top.

 

There's a bolt on top that goes through the plate the vacuum solenoids sit on. Then there's another bolt on the driver's side of the throttle body. It takes a hex bit. I can't remember what size. It can be kind of hard to see the first time. It can also be a pain to get to. Once you get those bolts out, you have to unclip the tube from the crankcase breather system that's attached to it and then it comes right out. I would try removing the flexible piece between the air box and the throttle body tube and see if you can get it from there. I did mine a while back but I can't remember how much I had to remove to get to it.