View Full Version : Strange coolant leak on my truck

May 08, 2004, 15:22
88 Ford Ranger. I'm getting puddles of coolant on top of the intake manifold. The thermostat and heater hoses connect on the front of the engine so that any leak there would run down, also no puddles on the ground. Where could it be coming from?

May 08, 2004, 15:26
Your sadistic neighbor carefully putting it there with a teaspoon?

Jim :fal: FALunga

Mosin Guy
May 08, 2004, 15:40
Could it be from your intake gasket where it meats the head surface??? My sons 1995 Grand Prix 3.8 liter V6 did exactly the same thing,he keep finding coolant under the car,but you could not see any evidence of the leak other than the puddle of coolant.

May 08, 2004, 15:43
Where at on the top of the intake? Any chance you could post a picture?

Could have a leak between the intake manifold and the head. I would look and make sure you don't have a hole in the tubes/hoses running to the firewall for the heater core.

May 08, 2004, 16:08
Motor size would help too..

May 08, 2004, 18:04
Engine is 2.9 litre V6. Heater hoses don't run across top of engine so they couldn't be the cause. I was thinking along the lines of a leaking intake manifold gasket too since there doesn't seem to be any visible leaks. It's been loosing coolant for a long time, but not enough to be worth fixing. I would top off the radiator every 2-3 months be happy. Now suddenly it's fine one day and the next day running really hot, there's also an actual puddle of coolant on top of the intake manifold, drivers side right about the middle of the engine, before there was just a trace you could see if you really looked for it. It's a beater so I don't want to put much money into it if I don't have too, but I am driving it to work so I need it to be reliable. I'm going to flush the radiator and try some stop leak first and then move on to somthing else if that doesn't help.

May 08, 2004, 18:11
i have a 98 chevy that did the same thing it was the intake manifold gasket good luck if you can do it yourself you will save much cash;)

May 08, 2004, 21:01
You may have a hose with a pin-prick type leak. I had a Ford with this problem once. If you have a timing light, set it up and use it after the sun sets to see if you can spot airborn droplets. Pulsing light is good for that purpose.

In auto repair, replace the cheap parts first.


May 08, 2004, 23:24
Hopefully it's just the intake gasket, however it will be worth the money to pressure test the intake while it's off. Ford aluminum intakes are notorious for cracking.


Da Nerd
May 08, 2004, 23:27
Drain your engine oil and see if you have water in it as well....if so, it is gonna eat up your bearings real quick.

Gunga Din
May 08, 2004, 23:33
Originally posted by Mahatma
You may have a hose with a pin-prick type leak....
This is good advice. It could be squirting there from 'way across the engine compartment from a pin hole leak that only opens when the engine is up to operating temperature.

May 09, 2004, 01:54
After driving and getting the engine really hot, stop and lift the hood whale the engineis running. I would bet a dime to a donut that your intake manifold gasket is leaking. If it is, you should be able to see where the water is coming from. Seem to be a common problem on the "newer" cars!

May 09, 2004, 09:44
Those kind of leaks are hard to figure out when you are there and even harder when all you get to see is the computer screen:shades: But, being that it is a Ford, although I have no experience with a 4-banger, I would tend to think it is either the intake gasket or a cracked intake manifold.

The best way to find out for sure is to pressure test the coolant system with one of those pump up pressure testers. Maybe you know someone who has one you could borrow.....or some of the parts retailers will lend them out for a deposit.

Good Luck on it.

May 09, 2004, 16:03
It sure sounds like you need to re-torque your intake manifold. I suspect that you have a leak at the coolant crossover in the middle of your manifold. You have coolant passages going from one side to the other for both engine cooling and warm-up American engines have some inherent 'shift' at times. This is due to some machining practices being less than perfect. Even though no re-torquing is typically called for, most foreign engines, especially the German ones require periodic re-torquing, notably the diesels. As a matter of practice, I've redone my intake manifolds and heads as a matter of course when I saw oil leaks from the lifter valley seals. Then did the heads. Solves a lot of problems. I would torque the manifold, then re-torque the heads. Keep in mind, you need to loosen the bolt, not just do a static tightening. Check the spect to make sure that you don't have a 'degree final' torgue setting. I.e. final tightening isn't measured in pounds, but degrees, such as 30, 60 80 degress of a turn. That should solve your problem. If not, you have a faulty gasket. Your engine heating up above normal indicates that you are having some combustion gases entering your cooling system. Probably not enough to show a lot of bubbles at idle, but some egress nonetheless. I'd take care of it asap, as it won't get progressively worse at that state, it will probably just let go and you'll be sucking coolant into your engine.