fire123

Hi Thanks for checking this out. So i recently had to bring out my 94 z28 a4 due to my winter car taking a crap on me. i drove to work the last couple of days no issues..however on my way home today i stopped at the store and when i got back in the car to go home. sitting at the light my temp gauge began to climb as i started driving it shot through the roof maxed out. i made it home as this was happening and shut the car off coolant audibly boiling in rad. I checked coolant level after it cooled down it seemed fine a little low, but not low enough for that to happen. especially seeing how its all of 30 degrees outside today. Id also like to add over the summer i had a whole slew of cooling issues ending in new rad new thermostat new coolant temp sensor and one other sensor. After topping off coolant i ran it for a bit and the temp still slowly climbed up didnt max but got high roughly 230. i tried running the heat it blows very poorly and not really hot. when switched to cold air it blows significantly harder...i remember this being a sign of something just cant remember what. Also on the way home coolant low light (which is on 24/7 never low just a result of all the stuff over the summer) shut off for a bit which was odd to me. one q i do have is should the cooling be visible in the coolant overflow at all times? ie is it too low if i cant see it not using the dip stick? and does anyone know what could be causing this cooling issue...once again.. thanks - adam

Scrub88

Did you bleed your coolant system of air ?
Cooling fans working ?
No heat from vents clogged heater core sludge rust and also sometimes is a symptom of leaking head gaskets
Correct lt1 t stat not the same as a 350 t stat and I keep my overflow tank filled to the correct mark on the dip stick

fire123

i replaced with the correct 180 t stat. Bled air after the replace back in the summer got steady constant streams of coolant through bleeder screws...however it was believed i still had a small amt of air in the system ( supposedly trapped in the heater core? i guess that happens) Just the main issue is there was no reason whatsoever for what happened earlier so i dont get it. Did not bleed when i topped today..just added to reservoir poured a little directly into radiator didnt think was enough to cause need to bleed. should I?

fire123

dont know if fans engaged when it maxed out earlier. i know they kick on at like 230/240 0n my car for some reason. Didnt hear it earlier when i let it sit running but idk if it was quite high enough for it. kicked on the ac and it dropped my temp gauge due to the fan throwing on

LT1553

I would def check the fans. I had the same issues with my 95 Formula, found out that my PCM had gone bad and was not engaging fans at appropriate temperature. I ordered a mail order tune and when I replaced PCM it fixed my overheating issue. Good Luck!

fire123

New PCM in car, and good news - heard the a fan kick on just now. Gauge rt around 230 i guess...so perfect. Just went outside topped off rad and overflow. Bled system properly (no jacking of the car however) gauge sitting at 180. Fingers crossed for the trip to work tmrw! MY only concern is i just dont know how this happened..how it got low..no coolant in oil or vice versa new water pump no leaks new rad no leaks. Dont know how it got low been fine for a week. Stored since oct thats about it.

Scrub88

Well just keep an eye on it see if it returns