Overheating and Coolant Loss

[warrier04]

So Friday morning the car is working fine. Normal driving, everything is grand.

Friday afternoon comes about, and I'm caught off-guard - my A/C isn't working. The blower is going about its business, but not cold air.

Weird, I think, and I just turn it off and keep going.

Farther down the road, I notice that my engine temp. is extremely high - near the 'H' on the dial. I pull over, and I pop the hood.

The coolant reservoir is bubbling, and there is coolant coming out of the little overflow rubber pipe. I look for any obvious leaks at the top and bottom of the radiator, but nothing appears to be wrong. After the car cools, the reservoir (which was rather full when the car was initially turned off) is now almost completely empty as the radiator has 'sucked' it all in.

I let the car sit until this morning (I was out for the weekend), and the same thing would happen.

Weird thing I noticed ...

In driving down the road, just casual cruising out of boost, the temperature would steadily rise. When I was in boost (any gear), the temperature gauge would steadily come down.

I have no real clue what to check out. It's like the car is only getting coolant when it's being pushed (like in boost), and other times, it's coolant starved.

Ideas?

[peajay]

thermostat, water pump or restriction in the line. check to see that your condenser is free from crap stuck between it and your radiator (thus causing reduced air flow)...those would be my first places to start looking.

[mspHtown]

a few months ago my thermostat went out.

the night before i ran the car pretty hard and everything was normal. the next day i was dropping my girlfriend off and on the way home (normal driving) the temp gauge shot up so i pulled over. coolant was pouring out of the overflow tank. i let the car sit and cool off. the coolant went back down and the temp decreased. i drove it another mile to my house and the temp started to go back up. i grabbed another car, bought a new thermostat at oreillys and problem solved.

[warrier04]

that's what my dad and i narrowed it down to - thermostat, water pump, or somethingi much worse that i have no idea what it is.

appreciate it, ya'll. sounds like i have a few options to try out.

[jeremy1210]

i seem to have a similar problem. If I'm sitting still with the a/c on the car blows hot air, but once I'm moving, it is nice cold air. Let us know what you find out cause I'm kinda worried about this as well

[warrier04]

for me, it was the thermostat. overheating stopped and a/c worked again.

[crackerjakx]

Seems like the stat taking a shit is becoming more common.

[o3t25msp]

similar situation here except when my overflow was boiling it ended up being my waterpump and not the gasket like i expected once removed i noticed that it was the impeller seal.. so during that replacement since timing belt was off i decided to install a coemetic thick head gasket and arp studs since ours are known to fail under higher boost and installed replacement t-stat until my b-spec t-stat arives.. but now i have a new situation with everything reassembled and pressure tested for leaks everythings fine.. i take it for a spin and after about a half hour of driving in 85 degree weather temp starts to rise (note: no a/c problems in either scenerio nice and cold) i check my pda for actual temp that computer is seeing and its 235 i get home shut her down pop the hood everythings fine and i look at my radiator cap which has a built in thermometer was only reading 210... turning heat on high also brought inside gauge down took out cts and it tested fine.. any input would be very helpful..

[dirtysouth_msp]

Did you guys test your cooling fans? Just a thought. Also check for oil in coolant and vice versa. Also, check both coolant and oil for exhaust gas smell. Headgasket would be like a worst case scenario.

[o3t25msp]

everything works for me like i stated head gasket water pump t-stat and radiator and fans are all upgraded..

[dirtysouth_msp]

everything works for me like i stated head gasket water pump t-stat and radiator and fans are all upgraded..

Yeah, that was more directed towards the other guys in this thread. Your situation is a lil different. Are you running a FMIC?

[o3t25msp]

i am running a fmic.. but have been practically since i bought the car and i make sure to keep it clean..

[buttthrax]

I think my thermostat has taken a dump. 2002 P5 ~86k miles. I'm going to take the thermostat out and see if the overheating stops.

I just hope it isn't the water pump. I'd rather jump off a cliff than replace the water pump right now.

[Captain KRM P5]

Seems like the stat taking a shit is becoming more common.

the msps are also reachinng higher mileage. a thermostat is a common wear/replacement item on many vehicles when you start getting more miles on them. for the most part, stock replacements are dirt cheap and relatively easy to replace.

[buttthrax]

Took out the thermostat and problem solved. No intention of buying another until winter because I'm a bum.

[o3t25msp]

Took out the thermostat and problem solved. No intention of buying another until winter because I'm a bum.


your running no t-stat at all? do you even reach running temp anymore?

[buttthrax]

your running no t-stat at all? do you even reach running temp anymore?

It does but it takes significantly longer. In fact so long that it throws a check engine light (I had it checked at autozone).

Damn OBDII crap.

[Brian MP5T]

I also run Sans T-Stat..

[buttthrax]

I also run Sans T-Stat..

Does it throw a check engine light for you too?

I'm just too much of a bum to spend the $10 right now.

[Brian MP5T]

No

I control it with a separate fan thermostat.