I was about 90% sure my head gasket was blown. I took it to a guy and he checked the compression and all was good. He found coolant in the throttle body. I have just installed a supercharger about 2 weeks ago, only putting on 200kms and then it started running ruff and it almost overheated due to coolant loss.

Has anyone run into this? Any easy way to test the throttle body for a leak? Do I need to replace the throttle body?

 

Not sure about Toyotas, but on Hondas and Subarus you can bypass the throttle body from coolant lines. If you live somewhere that gets cold during the winters, you probably don't want to do this.

 

I bypassed mine for a while, just disconnect both lines going to it and then use a barb to barb connector with little hose clamps and connect the two rubber tubes together. Then plug the holes in the Throttle body to keep dirt out (may not be necessary but I did it). You might find the leak was just the hose going to or from the TB and not the TB itself.

 

what engine?

 

If its the 3.4L, the coolant hoses go through your IAC, which is attached just below your throttle body to adjust your idle. There is a small gasket in there that is probably old and starting to leak...Or, you may have just nudged those lines just a tad during your installation.

If you pull off your throttle body, you'll see 3 hoses going into the bottom. the upper most is a vacuum line, and the bottom two, which appear to run in series with each other are the coolant lines.

 

Its the 3.4l. I have someone looking at it and he thinks its the gaskets below the intake plenum as it was falling apart. He changed it out and put everthing back together. After running it for a few minutes, there was less white smoke coming from the exhaust. The engine still had a shake to it, it sounded like it was misfiring. He said the plug has probably gone bad due to the coolant (IK22). Today he is going to change that plug and use my old on to see if that solves it.

The only thing that baffles us is he said he found coolant in the throttle body area?? He looked at the throttle body and did't see how the coolant could leak from it.

 

How about where the little rubber hoses connect to it? Is it that far fetched that one of them might leak?

 

x2 these do run a coolant line through the bottom of the throttle body.....

 

If the hoses did leak, how would coolant get on the inside of the intake and throttle body?

 

Update: He thinks the head may be cracked as it is still leaking coolant into the third cylinder. He thinks the gasket is okay since the compression test is okay. Would a crack in the head be visible if the head was taken off? Anyone know how much a new head is?

Oh, and he said my rad is leaking! I'm not happy.

 

The only thing that baffles us is he said he found coolant in the throttle body area??
this means in the throttle body??? to me it means under the throttle body...
if the coolant is in the throttle body you may need a new one...or to see of you can rebuild the one you have...
sounds more like under the throttle body and that would be a simple replacement of the lines...

 

Cooland?

 

Inside the throttle body! He first thought it was just the throttle body leaking internally, but as the looked further, he noticed it was only in 2 cylinders, he could see coolant in the intake plenum???

 

A crack can sometimes be hard to see, but there are ways to detect them.

 

which 2 cylinders??? one side?? one each side??? the ones below the throttle body???
This could even be caused by a bad intake gasket....I do not remember if the plenum gets water induced in it as well....

 

This is Mark's (midiwall) cracked head. Looks like they didn't see the crack until they started machining it.



I think sometimes the cracks will only open up good when the engine gets hot.

 

It is a bad head gasket. I'm going to get the heads redone. There is some pitting on the block. Here are some pics of what it looks like. What can I do about this? The guy working on it said he could put some gasket schellac on it. The gaskets were in rough shape, I'm sure the supercharger helped blowing what was left of the gasket. I'm thinking of removing the supercharger and selling it to cover these costs.

 

Yuk...that's not good. Looks like maybe it was run with straight water for a while, probably tap water.

 

Any ideas what I can do? I couldn't even get my heads done locally. I had to send them out.

 

I would suggest calling around and see if you may be able to find a machine shop to do this... other options are really not that great!!!

other options like steel wool or a belt sander... really do not suggest a belt sander...

you may be able to find a gasket to fill the void and use some steel wool to buff as much as possible out...

however there are tools designed for this but they are not cheap and you would prefer to practice on some thing you are not concerned with first!!!

junk yard parts or some thing

if I knew you were sending the heads out first I would have suggested trying to find a new engine first!!! still may be able to and swap the heads, or not swap them till you need to!!

Black RTV is an option!!