First, what a great site, one of the most informative ones around.

I have a 1990 4Runner, Auto, 3.0 that is using 1L of coolant every 2-3 days. I took it to Toyota, thought it was the HG, they checked it all out and said that the HG is good and that there must be a leak under the intake manifold. Has anyone had a problem like this and how to fix, $1000 estimate from Toyota. I did a search but could not find much.

Thanks for the help.

 

do a search for "gas smell" and you'll find the procedure on how to get at the fuel injectors to replace the o-rings. There's a post somewhere that will give you the steps necessary to remove the intake manifold.

-socal

 

http://personal.utulsa.edu/~nathan-buchanan/93fsm/

online factory service manual. Pulling the intake is pretty easy

 

oh yah. welcome to YT

 

Thanks for the quick reply.

Once I have the intake manifold off is there an easy way to find the leak? Does it even make sense that there is a leak under the intake?

Thanks

 

If there is a leak under the intake manifold putting out 1L of coolant every 2-3 days, it will be visible somewhere. Ever see any puddles under the truck? Ever see any steam coming from your engine compartment? If not, then it's not sounding like an external leak. Did they pressure test your cooling system?

 

Toyota did not do a pressure test, they took out the spark plugs and used a scope to look in the cylinders. They said that if there is a HG leak there would be a residue on the cylinder walls.

I still think that the HG is going.

 

I'm in the middle of chaning the head gaskets on my 93 PU with a 3VZ. The obvious indication that the gasket was blown was the white smoke of the exhaust and the odor of the exhaust. The white exahaust smoke was most prominant after a cold start. Although as your dealer pointed out, this could be a leak into the intake. However, It seems far more likely to be the head gasket imo.

 

I had/have the same problem. Coolant was leaking down from somewhere. No one found the leak so we added "coolant metal" .works for now but i do not know how long it will last.
Might it be the HG ? The engieen has never ran badly or anything.

 

if im not mistaken, there is a tube that runs from the back of the waterpump to the rear of the engine under the manifold. If there is it could be the seals or the tube itself rusted through. Sorry for being vague, its been a long time since I had a manifold off of a 3.0