98 Cavalier 2.2L ~130K miles

Pulled out of the garage a couple of weeks ago and saw a large puddle on the floor. It was coolant and it's been leaking kind of irregularly. Some mornings I'll pull out and there will be a large puddle, other mornings hardly any (more often than not though). It took about 2+ weeks for the warning light to come on, so I added some yesterday.

I've tried, but haven't been able to find the leak. Underneath, there's an exhaust bracket near the cat that the coolant is dripping from, and there's some kind of other bracket right next to it where it's also dripping. It's definitely coming from the passenger side of the engine. (I know - very enlightening)

One problem in finding the leak is that the engine is pretty covered in oil from about 5-6 years of a old valve cover gasket making a mess, but it's so baked on that the coolant still looks clean when sitting on the garage floor. I asked AAA to look for a leak while I had it over there for an oil change and inspection last week, but they didn't seem to believe that I had a leak, much less find it.

Questions: is there one or two places more likely to leak coolant than others? is there a recommended shop somewhat near the intersection of six forks and wake forest i could take it?

I feel pretty comfortable replacing things on the car, I'm just having trouble locating the leak.

3/9/2009 9:42:28 AM

Hmm... Maybe it's a bit like my first car (1990 Jeep Cherokee Laredo). It had a small hole in the radiator that would barely drip while the car was cold, but once it warmed up and we got rolling it would leak antifreeze all over the damn place. The dealership almost didn't catch it until we reminded them to drive the car around to warm it up and THEN check it. Needed a new radiator. So yeah, warm it up and give it a good look and I bet it'll be a little more apparent where the leak is.

3/9/2009 1:49:40 PM

Ten bucks says if it's not one of the heater hoses, it's the water pump. A lot of pumps won't really leak a whole lot when it's warmed up and under operating pressure (between 13 and 16 psi) because the pump seal is under pressure; it uses a spring-loaded positive seal. When the system starts to cool off, and pressure subsides a little bit is when it really starts to leak because there is insufficient pressure on the seal faces.

Once the seal becomes worn out enough, it will leak more under hot/operating conditions. Sounds like it's time to replace that pump.

3/9/2009 2:21:58 PM

^^ it doesn't leak at all until the engine has cooled down... if i park it, i won't see anything, but i can see it dripping slowly the next morning

^ between those two, the leak would appear to be closer to the water pump than to the heater hoses (based on where the puddles appear)... i might just go ahead and replace the pump and see if that fixes it

i appreciate the help

3/9/2009 9:12:31 PM