Rare coolant leak....looked over 99 percent of the components.

[pshabou]

Hey everyone!

So I have an issue. I have a 2004 grand prix, I am the only owner and have done 99 percent of the repairs myself and it has 300,000 miles but drives unbelievable and drives brand new. I am a DIY guy and have replaced tons of stuff on this car myself as simple as brakes and as hard as the rack.

The problem:

I am leaking coolant, under the car near the passenger side. I have recently had the high pressure power steering hose replaced by a mechanic because I didn't have time and needed it done quick, the coolant is leaking somewhere near that area where it attached to the power steering pump. I have checked the water pump with no leaks and its new with about 5k miles on it. Radiator is not leaking, all the big rubber hoses that the radiator sends and receives coolant are not leaking. The hard plastic elbow's are not leaking. The hose connecting the reservoir is not leaking. Radiator is not leaking. The hoses that go into the firewall are not leaking (both). No white smoke from the mufflers and no foamy oil. I recently had a pressure test done on the motor, and the gaskets are good.

Heater does not blow out very hot air, it is luke warm at best. Is my heater core cracked? Water leaking to the bottom of the car and draining thru a hole of some sort on the under-body?

I am going insane, and just came inside, with the temp. getting warmer, I need to figure this out. I do have other cars to drive but love this one as my daily driver.

Love it if I am over-looking something quick and easy, I am thinking the heater core or maybe the mechanic who replaced the power steering hose knocked something loose. It happened right around the same time that was repaired.

Paul S.

[BillBoost37]

Paul...

Did you run your finger on the firewall side of the connections where the heater hoses meet the alternator bracket? The hose connects to a fitting, the fitting then is held into that bracket by a 7mm or 8mm bolt (loosely I might add), and the fitting... has an o-ring on it that is what seals it to the atlernator bracket. This is directly above the power steering pump.

The other possibility is to check that the freeze plugs in the block of the engine are not leaking.

[pshabou]

Thank you for the quick reply!

I did run my fingers near the alternator bracket with no fluid. I have not checked the freeze plugs, I will check those now.

I might add, the coolant is basically streaming out, it is not a drip or a slow leak. It is almost like a small steady stream.

Paul S.

[pshabou]

I just read that the Engine needs to be pulled to replace the freeze plugs on the back side of the motor. No way I am doing that. That is too big of a job for the condition of the car.

[bobc455]

Did you confirm that's where the leak is from?

[coolone]

Degrease engine, fill er up and get under there to see where the leak is coming from. No guessing... Or pressure test the system and find the leak that way. Could be a lot of things, some simple, some not. If 300k, I would just look for a JY engine if not an easy fix.

[99GT2dr]

Too big of a job for the condition of the car... that condition being driving like new and unbelievable?

[paedbo]

use dye and a uv light.

[pshabou]

Hey guys, yeah It is the freeze plug on the back of the engine. Thanks for all the responses.

The drives awesome, of course I have maintained the crap out of it. I have replaced everything on this puppy at least once if not twice. I will let you know what I decide to do....it is not looking good, I do not have the time to pull the motor out to replace.

Paul

[Scottydoggs]

this has been done before, if you can get your hands back there and pry the old plug out you can then use a block heater to seal the freeze out plug hole (engine still in the car) its how a block heater is installed. they are under 30 bucks.