Exhaust leak

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Oct 22, 2003
Juneau, AK
I seem to have a minor exhaust leak coming from the manifold or gasket and have a couple questions. First, is thre any harm in ignoring it? Does the intake manifold have to come off to get to the exhaust, is it common for the gasket to blow or more likely to be a crack? One more question on another subject. What does the cold start injector time switch do for us? Thanks.
I'm driving a tank, otherwise known as a 1989 FJ62 with the 4.0 I6. It's my dream machine!
Well, exhaust leaks around the manifold can cause burned valves, and they sure can't be good for the driver.

Mike S
COld start injector time switch does just that. Times the cold start injector. if it is bad you get rough starts or really good starts and rich idle. How do you know it is bad? Code? If so just buy a new one. None of that stuff is expensive from the dealer.

On the 62 I would look at the exhaust doughnuts first. Usually they leak. Ex manifold is a rather major undetaking. While you are in there there is a bunch you should do.

In/ex comes off is mutl part. You also have the fuel rail to deal with. It can be done and is around a 3 bannana job but you need to do a bunch more while you are in there.

If I was to go that far with a 3FE I would go ahead and have the head rebuilt. You are only a 1/2 hour away from it.
Definitely check the donut first. Blown int/exh gaskets are fairly common especially in the 60 series. If you want to check for leaks you can spray some wd-40 around the manifold while the truck is running. If you have a leak it will usually kick the idle up alittle. First try tightening the manifold bolts, sometimes that works too.
another thing that could happen is that when it's start getting cold, the air will cause moisture and rust of it. I had the same problem not to long ago, I was going to fix it but I went wheeling and busted my whole exhaust I actually bent it and pulled it from the manafold. So i had to have the hold thing replaced anyway.

Well, this leak is a "tick, tick, tick" that's not too bad even when cold, so procrastination, rather than action, is my operative word for the time being. Thanks to everyone for all the useful advice and suggestions. Rebuilt head- gotta love the beast-yeah!
mine goes tick tick tick too, i was told it would kill mileage and power, any truth to these rumours
Your concerns would seem to make sense, although I wouldn't be the one to confirm them. I've never driven another 3F-E to compare mine to, but my power seems pretty good. Definitely a step up from the 4cyl powered Nissan and Toyota 4X4's i've been driving lately. I've been told to expect around 11MPG driving around my town. Just filled er up for the first time and got 10 (hence the username), but expect a bit better next time.

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