coolant leak issue [Archive] - Forum


View Full Version : coolant leak issue

01-26-2011, 09:56 PM
i have a 99 grand am, just replaced head gaskets and intake gaskets last year, my car used to maintain 190 degrees as long as i put coolant/water in it whenever it started to over heat. i had to refill it every weeek or so. now its so bad i have to fill the resivour b4 i go anywhere. but now it overheats to abt 220 then cools down to abt 170. in the time of all this i have no heat untill it reaches 220 and starts to cool down, i remain to have heat for a good 10secs after it reaches 170, then no heat till 220 and it starts to cool again. no idea what the prob is. im thinking the thermostat but i replaced it when i did my heagasket last yr. but i still have a leak. what part does the cap on the resivour have? my caps crappy and i cant actuallly get it on right... maybe pressure in the resivour?

the car is rigged to have both fans on at all times when the car in on by a wire going to the abs fuse. how may i fix this?

if u have any suggestions please let me know.

01-26-2011, 10:14 PM
Well, anywhere from 190-220 is normal temps for this car. 220 isn't over heating. The stock computer isn't programmed to even turn the fans on until 230 unless you are running the A/C. Not getting heat from the heater though certainly isn't normal.

It definitely sounds like there is a problem with your cap. The cap on the reservoir is actually like the cap on a radiator in an older style car, and it holds pressure in the system (15psi actually). If the cap doesn't seal properly and/or is faulty and won't hold pressure, then that lowers the boiling point of the coolant and also allows it to expand more, which would cause it to be vented from the reservoir.

First thing I'd do is replace the cap, and if the threads on the reservoir look mangled or the opening is deformed at all replace it to. You might want to just replace both anyway, they are cheap. Refill the system and bleed the air out. If it continues to loose coolant and/or you still don't get any heat inside, then the problem is probably something else. Fix the most obvious and cheapest problem first.

01-26-2011, 10:53 PM
i shall try this tomorrow after school. idk if its the resivour or cap but one of they is stripped and takes me like 5minz to get it on right. also my belt whines for like 5mins when i start my car in the morning, think water may b leaking on it... my therm is 190. and always stayed 190. even with the fans on all the time. just took alot longer to warm up.