So, i took everyones advise and changed that coolant temp sensor in my 2.8 V6by the intake, that didnt help. Next i go buy a timing belt kit, water pump, and a thermostat. I just got done putting the thermostat and new timing belt, but when me and my buddy looked at the water pump and its pulley, it seriously looked brand new so we didnt put the new water pump in but did everything else. I fill the coolant correctly, i only opened one bleeder valve til that flowed but left the expansion tank cap off to let it bubble and givin it some revs to get the coolant movin. i let it sit for 5 min. and the temp guage still started raising toward hot til the temp light dinged and flashed at me again. Im lost guys, should i have done the water pump??? it seriously looked like new. by the way, the bigger coolant hose comin from the expansion tank is way hotter to even touch, but i can hold on to the smaller one that comes off the tank below it.??? Please help ive been without a car for too long now. Thanks, Andrew

 

Always replace the water pump! The factory one has a plastic impeller, if its not broke right now its gonna break damn soon. Whats going on exactly, after the thermostat opened and you topped off the coolant again andit still overheats?

 

Also when you installed your thermostat, did you install it with the nipple and the little steel ball straight upwards at 12 o'clock? If you installed it upsidown the thermostat won't open at the correct time causing an overheating issue.

 

If you have no record of the WP being done you should've replaced it while you were in there.

 

Yeah we put the thermostat in according to the manual, with thenipple up. and yeah the car was just idling in the driveway and it started raising to hot just sittin there.I knew it was a bad idea not to put the water pump in, but it seriouslylooked just as clean as the newone i had. should i juststrip it downagain and put the pump in? or is there anything else i should check??

 

This sounds more like a thermostat, so test that first.

Remove it, put in in a pan of water with a thermometer. and see if it opens up at the proper temp. If not, replace it. If the thermostat is good, then you must have a failed/blocked water pump, since that is the part of the system you did not replace. A failed coolant sensor wont cause the cooling system not to work, it just doesnt send the proper info to the car's ecu.
I guess another question is, when you had the radiator disconnected, did you run water through it and clean it out, and make sure its not clogged?

I would strip it down again, and replace the water pump, if the thermosat tests out, and you had verified the radiator is good.

 

i didnt really flush the radiatior but i have just recently had to run new coolant through it twice because of this project. What is the temp that the thermostat should open at when doing the test in the pan of water?

 

98f approx

 

Allright then, let teardown Phase 2 begin, you know before all this the most i did was basic crap like oil change, rotate tires, brakes, etc. this is crazy!!! i just didnt think i could handle it, but u guys have seriously been a great asset to have in helping me save a crapload of money. I'llkeep updating on the status of theA4.Thanks again, Andrew

 

that what the site is for im sure