Another weird coolant leak

[04silverprix]

Hi guys,

Yet again I have to deal with another bizzaire coolant leak on my wife's 2004 Grand Prix. The story goes like this: The coolant resevoir tank had a little leak and was leaving a puddle of anti freeze.

I finally got a new tank and cleaned the inner wheel well and installed the new tank. I filled the tank, started the car, let it warm up, and took it for a test drive.

Upon returning, I didn't detect any leakage around the tank and I figured the problem was solved.

Then I noticed a trail of fluid that run up my drive way and to the car in the garage. I crawled underneath the passenger side and found anti freeze dripping around the rockerpanel area by the sub frame. I wiped it and placed clean cardboard under the area. I got drippings on the cardboard.


Next I got a swivel mirror and my trouble light and looked around the passenger floor area by the bottom of the firewall. It was wet. I also noticed a trail of fluid that ran down the bottom of the passenger side of the car on the outer edge of what would be the frame rails if this car had a frame.


I can't think of any cooling system component that is anywhere near this part of the car. My fear is the heater core has sprung a leak, but it is located in the center of the firewall and I don't detect the typical heater core symptoms such as a smell of anti freeze inside the car or wet carpet.

I took my air gun and blew compressed air around the sub frame cavity and through the openings on the floor/rocker area. Maybe there was a build-up of fluid from the reservoir tank leaking.

I don't think I'm that lucky. Any ideas?

[Fivefingerdeathpunch]

Coolant elbows.

The one can be seem from up top, the other is kinda hidden on the back side of the tensioner/alternator bolt down thing.

Maybe the rear elbow sprung a leak.

[Scottydoggs]

if the fire wall is wet in the middle, check the heater hose's, as they tend to get soft and no long fit snug to the heater core pipe, and leak down the padding and drip out the bottom. mine only leaked after the car got warmed up.

take them both off and see if the ends are all swollen, some times you can cut the hose back a inch or two and be ok, but sometime you cant.

[BillBoost37]

If you think it might be the heater core, check the elbow on the firewall that drains the box.

[04silverprix]

Okay. I did a little further research and the firewall around the heater hoses is dry. The elbows are also dry. I did stumble across another clue.

I might have had too much antifreeze in the cooling system. I replaced the broken over flow tank and when my leak still appeared I put my finger around the drain pipe on the top rear area of the tank. I got antifreeze on my finger. I removed some of the coolant from the tank and cleaned everything up.

I ran the car today and so far I don't see any leakage. Maybe I added too much to the overflow tank when I replaced it.

[Rico]

There are indicating marks on the overflow canister. If your well above these marks the system will expand (when hot) and fill the overflow above the outlet for the spill tube. Check the level in the overflow when the vehicle is hot.

[BillBoost37]

Don't forget the slosh effect. They put the drain at the back of the tank on many years. I can get it to slosh out if it's a little high, using the pedal on the right.

[04silverprix]

Yeah roger that. I overcorrected filling the leaking tank while searching for the replacement. It didn't dawn on me while filling the new tank that I had too much coolant thinking it would have leaked more than it did.

At least it wasn't a heater core or something worse. Just me being generous with the anti freeze.


Thanks again for your help.

[BillBoost37]

Right..you didn't want it to get cold.