I am having some wierd problems with my coolant. Just for the heck of it, I checked the radiator and the coolant was low (where I saw bare metal up top). I checked the overfill bottle and I was dry. No biggie I thought and filled them both. I also looked over all the hoses and the head and intake and couldn't find any evidence of antifreeze. The next day I checked it again and the fluid was low in the radiator and not in the over fill. So I toped it off again. Well to make this post a little shorter, I checked the thrid day and the same thing. So I thought that there was air in the system and attempted to bleed it. I started the car and took off the radiator cap. Turned on the heater to high and topped off the fulid. Waited a while and checked. The dam fluid went down again. It opped it off let it run a little longer and It started to rise and "boil" over. I turned off the car and put the cap back on and let it sit for about an hour and a half. Checked it and had to top it off again. Drove home from the gf's house to check it and the cap wasn't even warm. Not hot, not warm, the cap was the same temp as the air lid. I am getting awesome heat and the gauage hasn't gone past the 210 degree mark. I most always check the spot from were I park just to see if I am leaking fluid,(oil, and what not). Sorry for the long post, but I wanted to give you guys everything that has happened. I don't want to mess anything up and I am kinda concerned. No leaks, car is running great and wonderful heat. What gives to having low coolant.

Thank for taking the time.

 

I would bet on the water pump seaping or another small leak.

The best way to test for them is with a pressure tester.

 

thanks for the reply. I jst checked it and its down again. Dam! Does it sound like anything else?

 

did you perform any work to the car before this started happening, or did it just start randomly?

Did you check all the hoses and whatnot?

 

I haven't done any real work on the car. I did an visual inspection and ran my fingers along the hoses to detect any coolant and didn't find any. I haven't really checked the coolant in a while. I just check the other day out of ramdom curiosity. I really don't know how long this has been going on for. If it is my water pump, wouldn't coolant leak out on to the ground and be noticable?

 

The only way you wouldn't see coolant is if you were only losing it while you were running, or you were eating it. Do you notice any smoke coming out of your exaust ?

 

no smoke that I have noticed and the car seems to be running great. The temp guage is working and only goes up to 210, and the heat is pumping out awesome.

I am really stumped.

 

Unless you have a 98, your temp gauge is a dumb gauge ... and will not reflect huge changes. It will give you an approximate, but normally hang around that 210 range.

 

Right, I have a 99 and haven't noticed any changes in the temp. I figured that if it was to over heat, the guage would move some what.

 

Personally ... I would drain your coolant system completely, and refill it properly.

Take the cap off BEFORE you start the car, fill it up, leave the cap off, start the car, let it get hot, fill it some more until it boils over. Let it idle for another 20 mins or so, top it off, the close the cap.

Let it run for another half hour or so, and see if you lost any coolant. Once the cap is closed, you shouldn't lose any. If you do, and it's not on the ground, you must be eating it somehow. The most popular places would probably be your throttle body or intake ... check to make sure all of those hoses and bolts are secure. If it's on the ground, it is most likely a loose hose, or something along those lines.
If none of this helps, you should probably bring it to GM and yell.

 

thanks for the help. I really do appriciate it. BTW, did you do a full interior swap? I noticed that you have ebony and not "dark grey". Did you swap EVERYTHING in the car.

 

Nah ... I guess you could call it dark gray ... I just called it ebony.

Btw, the drain screw for the coolant is on the passengers side, on the bottom of the radiator. It's a plastic little screw, that you just twist off.

Hope this helps and it works out for you.

 

Might want to check your oil and see if there is any signs of water in there. Worst case scenerio and would really suck but it just may be leaking into your motor.

 

Try another radiator cap, it could be that the water is evaporating and escaping through the radiator cap, The same thing was happening to my friend, he bought another radiator cap and problem was gone

 

I checked the oil dip stick and no signs of coolant or water. I was thinking it might be the radiator cap too. Is there a way to test for that. Also about how much is to replace. I'm gonna take it in for a prewinter check this saturday. Hopefully they can tell me what the problem is. I'll post an update when I can. Thanks everyone for your help.

 

radiator caps are no more than 20 bucks from autozone, my friend bought one of those old school style ones that is polished and he likes it cause it matches the a/c acumulator and the crankcase breather lol

 

I'm not sure if this is your problem. In order for the water to evaporate, there must be air leaving the radiator through the cap. I would think you would be able to hear the hissing sound or feel it coming out.

 

This same thing happened to me, it turned out to be a crack in my head gasket

 

Well so far the shop did a pressure test and from all indications everything came out dry. They were getting ready to close up shop so they're keeping her over night and check some more tomorrow. I keep you posted.

 

Ok, here's whats going on so far. I got the car back last night. I checked the coolant level in the radiator when I picked it up and it was a little low, so the shop topped it off. They said don't worry, drive it for a while and check it. Well I did. I drove around for a hour and a half. Got home and was able to take the cap off immeditaly. The coolant was topped off, but didn't over flow or boil over when I took the cap off. A little unusual right? Through out the night I keep an eye on it. I ran the car for 10 min shut off and let it cool down. The coolant would drop. I did this with the cap off. The coolant never reached the hole on the neck of the radiator for the overflow container. I did this 3 times last night. The last time I checked the car last night the coolant was just below the neck. I put the cap back on and went to bed. Before I went to work this morning I checked it again. I was down quite a bit. The overflow tank was fine, actually it read too full. Just above the full hot reading on a cold engine. I put newspaper under the car over night and checked it. Nothing appeared. So now my coolant is lowering while the engine is cooling and not going in the overflow tank. Its just too low to reach the hole. What can this be. The shop said that this normal, for the coolant to go down when cold. I agree, but not inches, not to where I have to get a flashlight pointing into the radiator to see the fluid. What can I go to the shop with and tell them to check. I am so pissed!