...just under the throttle linkage. My wife was driving it while I was out of town, and she called my cell 10 minutes before I was to board my next flight with the dreaded words, "The truck is hot and leaking stuff!" She let it cool off, then limped home before it heated back up (she said it wouldn't go over 35 mph), but it leaked more coolant in the driveway. I looked at the oil filler cap -- not milky. I filled the radiator -- it took approximately 6 quarts of water -- and started it up. Ran smooth, let it warm up almost to operating temp, no steamy exhaust, and no sign of any leaks, so I drove it around the neighborhood for 15 minutes or so with no overheating. But when I got home I checked under the hood and there was a pool of coolant/water just where she said she had seen steam and heard "hissing," under the linkage. It didn't look like much, but after sitting a half an hour a fair amount had leaked onto the driveway.

Head gasket was done at around 150K, but of course that doesn't mean anything.

Has anyone seen a cooling system leak in that area? Any ideas? Thanks in advance.

 

Two coolant lines go into the idle air control valve that sits right underneath the throttle body. The O-ring could have blown. I haven't heard much of that happening much but it sure sounds like thats whats going on.

It also could be the small coolant lines.

 

3.0, right Dogs?

Not a big knowledge base on that one from me, if so... but, from my book, it looks as if the water temp sensor and the cold injector time switch(both coolant related) could easily leak into the valley below the throttle linkage. I would think that's not as likely as some other things.... But I'm thinking from a 22re mindset, lol. Not sure if this has the same type Idle control as the 22re, either. If so, I guess that could do that as well. Mine leaked when I reassembled my motor, had to go in and snug it up. I wonder if your temp sender is there, too. I'd have to read up.

 

If it's not either of the above, there's a tiny u-shaped hose behind & slightly under the plenum that is the usual culprit for leaks. Do yourself a favor & take off the hood first! Only 4 bolts & a piece of cake to remove/install. You can access the clamps with long-handled needle-nose pliers.

There are also two small coolant lines that run through the bottom of the throttle body from the back & the front. They're a PITA to get in/out if you don't remove the TB.

 

listen to them, i just rebuilt my 3.0 and they're describing the only places for coolant to leak.


however i don't think the temp sensor or cold start injector time switch is leaking. it's likely a split hose.

 

Great ideas, thanks! I'll get into it tomorrow.

 

Update your sig, Dogs.... PLEASE? hahaha.... It can say, .......

"My wife was driving it while I was out of town, and she called my cell 10 minutes before I was to board my next flight with the dreaded words, "The truck is hot and leaking stuff!"

HAHAHA! That's great, but not as good as this girl we all knew, whom we TRIED, so hard to talk out of buying a Fiero.... She drove it a week, it blew up, the tow truck driver told her, "Maam, the oil light is on and flashing, and it has NONE in it...that's your problem...it's DONE, RIP!" She cried, turned to us saying, "It had oil when I bought it, didn't it?" HAHAHA! Good thing she thought to call you and then pull over, Dogs! Sweet, hope to see it fixed asap! Best wishes!

Mark

 

I'm going to take a pass -- I don't quite think that she wants to be remembered for saying that.

The good news is that it was a leak in one of the small hoses. I'm hopeful that no damage was done when it overheated. The 4Runner lives to fight another day!

 

I hear ya,....prob not a good idea! lol. Wise man! lol


WOOT WOOT on the fix! Best wishes!

Mark