I'm having overheating issues with my turbo DA. I drive the car far a full day's commute, boost a little, and it will be fine. Then, all of sudden I'll slow down as I'm getting home and the temp needle goes halfway and then up to 3/4. Sometimes it goes to max. This will happen spontaneously under high speed, low speed, boosting, and normal driving. Here's my status...

1. Just bought an OEM thermostat, going in soon
2. oil is not milky
3. radiator is about 2 years old
4. water pump is new
5. radiator fan comes on, it's also a higher CFM aftermarket one


If, worst case scenario, it's the headgasket, can I just replace it? Is there anything else involved with replacing a h/g? I've read about resurfacing the head or something to that affect. I do most of my work, but I haven't tackled a h/g before.

 

Have you tried bleeding all the air out the cooling system first?

 

I tried a couple of times to bleed the air out. I heard that if the radiator has a tiny hole, it could suck in air into the system. Is this true? The radiator is only about a year old and these problems started after I took it out and installed an aftermarket fan. It required putting these big fat zip ties through the fins. Is it possible that I punctured the radiator? Only thing is, I'm not losing any coolant.

 

when you bleed the coolant, leave the car running at idle, take out the radiator cap and keep filling the tradiator with coolant as it goes below the water neck line. sometimes you may have to leave it running for 30-45 minutes, it may take a while for the fan to kick in for the first time, but keep filling the radiator for 2-3 fan cycles.

I did this to DiRep's car and we sat and let the car idles for 45 minutes and which the fan comes on 2-3 times only and his overheating problems dissapear. His symptoms is similar to yours.

stan

 

sounds like a leaky headgasket.....I had the exact same problem and thats what it turned out to be. Does your reservior tank overflow??

Pulling the head isnt that hard, just make sure you have a helms onhand and a buddy who has done it before to give you a hand helps a lot too. If your engine bay is stripped down(no a/c, ps, cc etc) Itll be cake and itll take you like 3-4 hours. Add about an hour or two depending on how cluttered your engine bay is.

 

Well, I think I may have found the problem. Yesterday I looked really closely at the spot where I inserted the zip ties through the fins. When I moved the fan out of the way, I placed my finger there and there was a little bit of coolant. It such a tiny amount that I couldn't possibly notice if my coolant was low. I also don't think it's a coincedence that my problems started after taking out the radiator and installing the fan. Anyway, from what I understand, the reason the cooling system is pressurized is to enhance or raise the boiling point. I would think that if there was a leak the boiling point would drop?