Coolant Leak

Tiny
DAVISN95
  • MEMBER
  • 1999 CHEVROLET MALIBU
  • 6 CYL
  • 2WD
  • AUTOMATIC
  • 145,000 MILES
I have a 1999 Chevy Malibu LS, with the 3.1L V6 motor. I live in Wisconsin so the car sees very cold winters each year. Just recently I have coolant (dexcool) leaking somewhere out of the left-hand side (coolant reservoir side) of the motor. It is NOT leaking from the reservoir, radiator, or lower intake gasket). I know it is not the lower intake gasket because I had that replaced about 2 years ago already. The leak appears to be dripping off the left side of the engine block. What do you guys think? If you can come up with any diagrams that would be great... It is just impossible to get a good look at the left side of the block with the water pump housing and everything else in the way. The Hanes manual doesn’t give a good diagram of it either. Your help is greatly appreciated!
Monday, November 15th, 2010 AT 8:20 PM

34 Replies

Tiny
BSCHURR
  • MEMBER
  • 45 POSTS
The only cooling system component on that side of the engine is the water pump, Could be the water pump itself or the mounting gasket to the water pump. does it leak while running or when the car has been off? Check out his guide

https://www.2carpros.com/articles/car-is-leaking-coolant

Please run down this guide and report back.
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Monday, November 15th, 2010 AT 8:46 PM
Tiny
DAVISN95
  • MEMBER
  • 4 POSTS
The leak is dependent on the motor running. After I park the after driving it lets off a few drips. This is another sign that the leak is not a crack in the reservoir or radiator. It happens after flowing through those. If it means anything I noticed the dripping has slowed down. Last weeks it dropped a large puddle emptying the coolant reservoir. After that I filled it back up and since then has only been letting off a handful of drops when parked after running. I always keep a very close eye on the coolant levels before driving and while driving I keep a close eye on the engine temperature. It never overheats.
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Monday, November 15th, 2010 AT 8:58 PM
Tiny
ERNEST CLARK
  • MECHANIC
  • 1,730 POSTS
The proper way to diagnose a leak is to pressurize your system and look for the leak.

Pressurize the system to the psi rating on the reservoir cap. If you can't see the leak from the top, then jack the car up and look from the bottom.

Also, just because the intake gasket was replaced doesn't mean it won't leak. Not saying that's what I think it is, but don't rule something out until you've tested it.
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Tuesday, November 16th, 2010 AT 12:52 PM
Tiny
DAVISN95
  • MEMBER
  • 4 POSTS
Thanks for the help guys. I found the leak, it was the water pump gasket. The gasket was ate apart on the bottom side. I wound up replacing the water pump as well since I had it apart anyways and the new pump came with a gasket.
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Monday, November 29th, 2010 AT 2:53 AM
Tiny
ERNEST CLARK
  • MECHANIC
  • 1,730 POSTS
No problem. If you need anymore help, just let me know.
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Monday, November 29th, 2010 AT 11:34 PM
Tiny
BRANDON95
  • MEMBER
  • 3 POSTS
  • 1999 CHEVROLET MALIBU
  • 3.1L
  • V6
  • FWD
  • AUTOMATIC
  • 165,000 MILES
My coolant light was on so I went to buy some coolant and put it in and the light went off but a couple days later the light came back on so I check the coolant and it was all gone! I'm thinking there is a leak and I hope its not too serious because I have to travel this weekend for work and I'm scared that it will over heat! So do I keep coolant with me at all times! And the heat doesn't work all that is blowing is cold air!
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Wednesday, December 9th, 2020 AT 11:45 AM (Merged)
Tiny
JOHNNYT73
  • MECHANIC
  • 924 POSTS
You definitely have a coolant leak somewhere. These motors are very common to leak at the intake manifold gasket, but take the car to she a shop and have them pressure test it to see where the leak is. Also if you have it fixed be sure you have heat out the vents at idle. They can be a bear at times to bleed all the air out of the system.
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Wednesday, December 9th, 2020 AT 11:45 AM (Merged)
Tiny
BRANDON95
  • MEMBER
  • 3 POSTS
Do you think I will be okay to drive 2 hours if I put some coolant in and bring some with me! This weekend as I'm super busy with work! Because other then that it seem too be running fine its not over heating but the temperate gauge is over half but as soon as I put coolant in it goes back to normal and the heat works.

Thanks Brandon
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Wednesday, December 9th, 2020 AT 11:45 AM (Merged)
Tiny
JOHNNYT73
  • MECHANIC
  • 924 POSTS
I think you will be ok. Just be sure to keep it as full as you can with fluid.
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Wednesday, December 9th, 2020 AT 11:45 AM (Merged)
Tiny
BRANDON95
  • MEMBER
  • 3 POSTS
Alright awesome thanks so much! Very Helpful
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Wednesday, December 9th, 2020 AT 11:45 AM (Merged)
Tiny
SUSAN827
  • MEMBER
  • 1 POST
  • 1999 CHEVROLET MALIBU
Engine Mechanical problem
1999 Chevy Malibu 6 cyl Front Wheel Drive Automatic 59.000 miles

my car leaks oil and antifreeze
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Wednesday, December 9th, 2020 AT 11:45 AM (Merged)
Tiny
MHPAUTOS
  • MECHANIC
  • 31,937 POSTS
HI there,

You will need to locate these leaks, wash down the engine and run and watch for fresh oil leaking, check front seal rear seal, rocker cover oil filter and oil pressure switch as these are the most likely cause, as for the coolant, get a cooling system pressure test as this will locate any external coolant leaks easily.

Mark (mhpautos)
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Wednesday, December 9th, 2020 AT 11:45 AM (Merged)
Tiny
JENNBY23
  • MEMBER
  • 1 POST
  • 1999 CHEVROLET MALIBU
  • 6 CYL
  • FWD
  • AUTOMATIC
  • 175,693 MILES
1999 Malibu is leaking coolant bad! Not sure what the problem is. Mechanic A) say's it head gasket, Mechanic B) say's it's radiator. I fill it to the fill line one morning, by the next morning the warning light is beeping and the little plastic container I have under the leak is 1/2 full.
Not sure what I should do. I'm only using the car til my mom get's home, it's her car, but I have to take care of her apartment, plants & animals while she's out of town, and our second vehicle is a '97 Intrepid with almost 400K on it, school lesson car, engine is spotless, passed certification with flying colours, dream to drive, but we don't want to rack up to many extra miles. It's 20Km round trip from our home to my mom's.
Please help!
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Wednesday, December 9th, 2020 AT 11:46 AM (Merged)
Tiny
RHALL77
  • MECHANIC
  • 3,361 POSTS
Have the cooling system pressure tested to find the leak. It could also be a waterpump or an lower intake gasket. Dont over drive it and over heat the engine. It could damage something
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Wednesday, December 9th, 2020 AT 11:46 AM (Merged)
Tiny
GLENN HIPSZER
  • MEMBER
  • 1 POST
99 malibu 6 leaks coolant badly. The line that allows the coolant to fill to the top of the radiator was clogged at the inlet to the fill tank the tiny copper tube was full of goooo I used a long. 1/16 drill to clear it out leak stopped car really runs good now
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Wednesday, December 9th, 2020 AT 11:46 AM (Merged)
Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 54,149 POSTS
Great addition to this thread! Please feel free to help out whenever you are on the site :)

Cheers, Ken
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Wednesday, December 9th, 2020 AT 11:46 AM (Merged)
Tiny
TOBY224590
  • MEMBER
  • 1 POST
  • 1999 CHEVROLET MALIBU
  • 3.1L
  • V6
  • 2WD
  • AUTOMATIC
  • 135,000 MILES
I've had this leaks for about a year I just keep fixing it with liquid copper seal witch is the worst solution. Its some kind of leak at the bottom left side of the engine if your standing inform of a car. I don't like mechanics working on my car so I haven't brought it to any shops and I can't find anything online about it.
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Wednesday, December 9th, 2020 AT 11:46 AM (Merged)
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,796 POSTS
Good evening,

All that sealer does is clog up the radiator and heater core and never really does nothing about the leak.

I would rent a pressure tester and pump up the system and use a bright LED light to determine the source of the leak.

The lower left is the timing cover, water pump and it could also be the intake manifold gaskets as well. That is why you need a nice bright light to find the source under pressure.

https://www.2carpros.com/articles/radiator-pressure-test

https://www.2carpros.com/articles/car-is-leaking-coolant

Roy
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Wednesday, December 9th, 2020 AT 11:46 AM (Merged)
Tiny
DAVIDDALLIMORE
  • MEMBER
  • 1 POST
  • 1999 CHEVROLET MALIBU
I am loosing a reservoir full of coolant during a 40 minute drive to work. There are no visible leaks. However, my a/c smells like coolant, condensation is coming out of my defrost and fogging up my window, and hot water is coming out of my a/c drain hose. What in the world is going on? Call crazy, but I can not find the water pump either. Where is it? 99 chevy malibu, 155K miles 2.1L 4cyl
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Wednesday, December 9th, 2020 AT 11:46 AM (Merged)
Tiny
CANADIANAPPRENTICE
  • MEMBER
  • 18 POSTS
Hello,

two things, check your Heatercore, it is located under the passenger side of the dash, I would definately say it would be coming out of there. And the water pump it driven off of the belt.
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Wednesday, December 9th, 2020 AT 11:46 AM (Merged)

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