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Team420

ok...sorry...I prolly should have re-read this whole thread before posting.

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thook

Oh man, Dwayne.....aren't you going to test the old coolant sensor? I know it's running better......that's great, but I was trying to save you some money. In other words, I wasn't trying to encourage you to throw unneccessary parts at her. ("Christine".....that's funny.) The coil obviously didn't fix the problem, so your original is probably still just fine. The new sensor, didn't fix the problem, either. Do test the old one. If it is bad, keep the new one. But, I'd put the old coil back in and hang on to the new one until you actually find the real issue. When you've fixed that you can take the coil back.

If you've completely ruled out the AFM according to the test I'd suggested, it appears as though it is coming down to a mechanical issue. I hope for your sake it's not a burned valve. That would equate to a definite vacuum leak.....obviously. This has happened to my wife's '92. The motor that's in it now is a replacement for the first rebuild. The 1st rebuild was done under the original owner and then crapped out at 21k after we acquired it. Then, we bought another rebuild (the present) that I then had to rebuild because the builder kinda fubar'd the job. He either didn't get the valves set right, or it's because he damaged the cam rods and went ahead and installed them. When I'd taken the motor apart, I found two of the lobes on the cams were cracked and pieces of them had migrated through the head. Possibly one of those pieces made the valve stick....not really sure. But, I replaced those heads with the ones off the first rebuild being that they were in excellent shape and it fixed the problem at that time. There were other issues after that.....electrical ones from age, but those were eventually resolved, too.

I just want to say this.....

Sure you are spending a fair amount of money on this motor, Dwayne. But, consider that if you got another motor to replace this one (namely a 3.4), what would you do when something goes down with it? In other words, you buy it used, mechanically it's sound, but it's used, so how long will it be mechanically sound? Eventually you'd have to do some work on it, as well. So, in the long run, money is going to be spent. I suppose it could be argued that the 3.4 is more worthy of the investment, and that may be true with the gains in power and mileage, but getting this one running right and it's worthy of keeping. Then, later down the road, if you want to sell it, it will be sellable. (<<<Is that a real word? It just doesn't look right...hehe)

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thook

Oh.....I thought you meant the wiring connector.....not on the sensor itself. Bummer.

The thread is under "AFM testing". I go over what I did there, and it should be straight forward. I got a used one from Nix99. DeathCougar from YT works there. They're extremely helpful and only wanted $80 shipping included. If you want a brand new one, there is an ebay seller with quality units and a lifetime warranty. I'll have to get that link later. I'm gonna finish some things up around here and go to bed early.

Tah!

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thook

Ebay link.....

http://cgi.ebay.com/ebaymotors/ws/eB...K%3AMEWAX%3AIT

Um......I don't think they (Nix99) normally test the parts individually with a meter. I can't imagine they have time to actually do that. Plus, it would costly in the labor department. I do know that the vehicles the parts come off are guaranteed to be fully operational. And, if the vehicle isn't running they do make the sure the parts are atleast good. I guess you'll have to ask the details. Since I trust DeathBooger, I know he wouldn't sell me junk, and if there were ever an issue he/they would make it right.

And, you can tell him I said DeathBooger. He'll like that.

86-91-4runners

I also had missfire nightmares with my 3.0 4runner, the ecm will get confused if there is a vacum leak, a dirty connector, bad coolant sensor, along with lots of other things. The first time I had the problem it was traced down to the coolant sensor, replaced it and was good for like 6 months or more. And then again missfiring came back, this time it was a dirty connector. It was the one about 4/6 inches from the distributor and comes from the distributor and goes right across the front of the engine, cleaned it with a pick and some CRC contact cleaner, put it back together with some CRC Di-electric grease, and decided to unplug and check every other conector I could find and cleaned and lubed them all. No more missfiring for almost a year. Then it was time to chase a vacum leak, just went out and got 40 miles of vacum hose (yes the 3.0 has a million little vacum hoses) in the common size and several feet of the others and just started to replace all of it one piece at a time, took the whole weekend. Sure glad the latest 4runner has the 3.4 almost no vacum hoses in comparision. This time we where good for around a year. And then came the engine harness short, we could push on the harness in this one spot where the fuel injector leads are right in front and on top of the engine and the miss would go away for a few days and them come back, this was a fuel injector miss fireing all the plugs would fire but had what seemed like a dead cylinder wound up zip tieing the harness at this spot and that lasted for awhile. Opened the harness up to see about patching it and auh Oh crispy wires, soldered it patched it back together and starting looking for a new harness no longer avialable new so we found a used one in Colorado that was in really good shape opened up a small spot near where it would be subject to the most heat to check it out and wires looked new. Sealed it back up really good and installed it. It has now been nearly 3 years 34.000 mi and no more problems, TG. All those issues came between 135.000 mi to about 165.000mi and over about a 3 year period. And she has been a dream every since the harness was replaced. Just recently picked up a 96 4runner and sure do like the 3.4 But I think old blue will always be my favorite, its a 1986 4runner 22re we have had it just over twenty years about to hit 236.000 and the only issue has been an air conditioning compressor . Still has most all the origanal parts even vacum hoses, have done the clucth twice, timming chain twice, and rebuilt the starter twice. All oil changes every 3,000 mi and gear lubes every 18 mths, recently flushed the brake system for the second time. Long story short, there are a lot little things on the 3.0 that you would not normally think to cause a missfire, but the ecm relies on good signals from many different things. Try all the little stuff before spending big bucks. Good luck, and happy Yota trials.

Wes94

Thanks for the very informative post!

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TNRabbit

Slight leakage past the rings is what you are looking for that says you have a healthy cylinder, so you're good.
Why did you only check cylinder #6??

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Wes94

Congrats on making some major progress.

This thread is like CSI 4Runner!!

Sounds like you'll have Christine running like a champ soon.

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thook

AFM going OL on the sweep test is not normal. So, there's that. And, with the TPS unplugged the timing will advance. That will help an otherwise sluggish engine running too rich. In other words, there may be not be anything wrong with the TPS, if you suspect something is. But, did you run a sweep test on the TPS?

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