1999 Grand Prix Coolant Leak

GMC

JE

MEMBER
2 POSTS

I have a 99' grand prix with 172000+ miles that I passed on to my son a month ago, the car has been well maintained and running very well. After getting some kind of fuel pump replaced (that I was told was rusted) we noticed antifreeze on the ground. At first he had to replace the antifreeze 1 time a week now for the past 2 weeks he's had to put antifreeze in every day at $10 :shock: daily (the overflow bucket). I looked under the car today and saw where the antifreeze is coming from. There is a black plastic like thing over what i guess is the radiator and it has a hole in it, it looks like a cap may go over it so my question is..is there a cap for that? and also is it worth getting the radiator fixed if there is something wrong with it? or should we just get him another used car? considering the miles on the car... thanks

Mar 4, 2006 at 2:23 AM

JPAM

✓Experienced Mechanic
307 POSTS

were about is leak located?? is it right around lower hose?? it just might be drain valve fell out.. take alook and see.. I would get it fixed it would be worth it.. thnks and let us know jess s.

Mar 4, 2006 at 5:36 AM

JE

MEMBER
2 POSTS

hey...and thanks for the reply. I'm not sure exactly where the leak is coming from but I will definately crank the car up to see. From what I saw without it being cranked up the leak is coming from the front driver side near the front. When we poured coolant in the actual radiator saturday we could hear it go in and spill out. Where ever the fat black pipe lead to I'm assuming thats where the leak is. I will check while its up wednesday and tell you what I see. Thanks....Je

P.s. I'm a little worried about taking it in to be looked at, I'm a female and often mislead. I was told once I couldn't buy 1 tire for my car and that I had to buy 4, I thought it was strange but of course they convinced me so I did.. :cry:

Mar 6, 2006 at 1:22 PM

MVANNESSJR

✓Experienced Mechanic
223 POSTS

From your description I would lean toward a lower radiator hose or drain plug. Let us know what you see!

P.S. You should atleast buy tires in pairs to keep the tread level.

Mar 6, 2006 at 2:05 PM

RUGRUV

MEMBER
45 POSTS

you need to findout where the leak is. Look carefully at the radiator. Look at the two big black rubber hoses leaving the radiator going to the engine. The side of the engine with the belt and pulleys is where you'll find the water pump. Water pumps will often be sources of coolant leaks as the seal wears out.

In the close quarters of the engine compartment it can be hard to see the water pump leaking and you may only be able to see it well when the engine is running. looking up from underneath might be helpful.

Mar 6, 2006 at 3:00 PM

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Suggested Repair

Locate the coolant leak before replacing the car. Inspect the lower radiator hose, radiator drain plug or valve, and water pump, including a look from underneath with the engine running. Repair or replace the leaking part; experts said the repair is worth doing despite the mileage.

Conversation Summary

A 1999 Grand Prix with over 172,000 miles began losing coolant after a fuel pump replacement, progressing from weekly to daily top-offs. Coolant appeared to spill near the front driver side around a black plastic or hose area by the radiator. Experts advised finding the exact leak, checking the lower radiator hose, drain plug, and water pump, and repairing it rather than replacing the car solely because of mileage.

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1999 Grand Prix Coolant Leak

Suggested Repair

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