sudden major coolant leak 3.1 litre SE

Hello,

1999 Grand Prix SE 3.1 litre engine 172,000 miles. The car suddenly started dripping coolant from the passenger side rear engine area. I have been watching the car closely since changing the water pump last week and until today absolutely no coolant leak. The leak is pretty bad when the the car is running. I brought it into the local pep boys for a diagnosis. They are saying that antifreeze ate through the timing chain cover and it needs replacement. They want a lot of money to fix and cannot even give me a price for the cover because it is a dealer part.

I read on another post about plastic elbows behind the tensioner that sometimes fail and can result in this type of leak. My question is do these exist on the 3.1 engine or is it just the 3.8 that has this problem.

Any thoughts are appreciated.

Hi,

I've never seen a 3.1 engine so I don't know if it has the plastic elbows too. But I think the Lower Intake Manifold gaskets might be your problem.

Look under both heads to see if the coolant is coming out from there. Did you inspect yourself around the timing cover?, your problem might only be the gasket since there is no reason for the cover to start chewing itself.

Oscar.

Thank you for the quick reply Oscar

It is not leaking that high up on the motor, and it is only dripping from the rear of the passenger side. Both heads are totally dry.

It is hard to see exactly where the drip is coming from..that's why I took it to the shop. I am suspicious of their diagnosis because they also want to replace one valve cover gasket for almost $400.00. They do not specify which one. They also recommended changing the water pump, which is not leaking and appears new...I replaced it last week.

Thank you for the quick reply Oscar

It is not leaking that high up on the motor, and it is only dripping from the rear of the passenger side. Both heads are totally dry.

It is hard to see exactly where the drip is coming from..that's why I took it to the shop. I am suspicious of their diagnosis because they also want to replace one valve cover gasket for almost $400.00. They do not specify which one. They also recommended changing the water pump, which is not leaking and appears new...I replaced it last week.

you need to get out of that shop!!!
i dont think the elbows are used on the 3.1 but not positive
i'd have the system pressure tested by a well known shop should'nt
be to tuff finding under pressure
400 for valve cover gaskets??? sorry 1 cover gasket?!$#%&*%%

It sounds to me like they are trying to steal money from you or they are just guessing.

I remember seeing a post about a common leaking point on the 3.1 engines. I'll see if I can find it for you and post it here.

Oscar.

Are you certain that the coolant is coming from the engine. The drain for the heater core is located on the firewall on the passenger side of the engine. The leak would be worse when the engine was running and would stop when it wasn't except for a few drops. Check the area along the firewall on the passenger side to see if that is where the leak is coming from.

Yes it is coming from the timing cover I saw it with the car on a lift. I talked to the head mechanic today and he redid my estimate ( there is no reason to replace the valve cover gaskets to correct this issue or replace a brand new water pump.) As Oscar stated it is probably not the cover itself but the gasket that is leaking.

The only problem was the gasket itself not the cover. A very sudden failure as I had been watching the car closely for leaks after I did the water pump and it was bone dry for a week. The shop fixed it for a reasonable price after I talked to the boss. Would have posted back sooner but I just got back from vacation. Thanks to all for the replies.