Can anyone help???

[PalmettoFJ62]

First off I just want to say thanks to everyone in this forum, i have been reading and learning for years now. You guys are awesome and are the reason for my cruiser infection. I have not had a single problem i couldnt come here and figure out a solution to just by reading old threads.

That being said i am to a point of great frustration with my landcruiser. I have a 1990 FJ62 with 3fe. Engine has about 80,000 on it and everything else about 170,000.

The issue i am having has been going on for about 4 weeks now. The engine turns over and runs great. The problem only occurs after its warmed up. I have about a 20 minute highway commute everyday for work. When i stop at a redlight after the 15 miles on the highway the engine idles a little rough but only some of the time.

When i go to accelerate the engine stumbles, spudders, black smoke out of exhaust and sometimes surges. I can usually just rev the engine and after about a mile of her wanting to stall and spudder shell run great untill i have to stop again.

Today it got worse. I stopped at redlight after driving some back country roads and she idled just fine. When i tried to accellerate the engine stalled. She will idle just fine but whenever i try to accellerate she stalls.

Here are the parts i have replaced.

Throttle Position Sensor
Intake hose,(cracked and chunks missing)
O-rings for fuel injectors
fuel dampener
fuel pressure regulator
intake manifold gasket
Fuel filter
New spark plugs
New wires

The only thing left i can think of is the fuel pump.
This being the most expensive of the parts. With the problem being only after the engine is warm and has been running a while I didnt think it was the fuel pump. The check engine light only comes on while the problem is occuring then goes back off when it stops spuddering.

Am i just this much of a cruiser noob??? Can you guys think of anything that i could be missing??? Sorry for the long post just wanted to make sure i provide as much information as possible.

 

[longtimecruiser88]

Hmm... try the coil I had a problem where all of the oil leaked out of my ignition coil and it burnt up try looking around the coil and pull the wire off of the coil... look for oil coming out of it. PS don't try accel coils I burnt out two of them, I think due to the fact that the coil is slightly inverted. Hope this helps

 

[PalmettoFJ62]

Hadnt thought of that thanks longtime will go check that now.

 

[Front Range 4x4]

Unfortunately the FP isn't the most expensive part. Have you pulled codes? That's really what you need to do since it may point directly to the problem.

It sounds like the Mass Air Flow to me.

Here's everything you need to know to pull the codes: Trouble Codes

 

[Kurtis]

Sounds like a mas air flow sensor to me as well. You can try to clean it with mas air flow sensor cleaner but usually it ends up needing replaced.

 

[PalmettoFJ62]

I have checked multiple times but there are no codes. Would a faulty coil cause intermittent problems like this?

 

[Kurtis]

It really sounds like
A. Clogged cat/ bad 02 sensor giving the computer a faulty reading causing it to overcompensate with fuel.
B. MAF sensor screwing the whole mixture up. I might start with the 02 sensor as that is cheaper.

 

[waiting for time]

You might also check for air leaks somewhere on the intake side.

Good luck,

 

[PalmettoFJ62]

Kurtis, that makes sense as the problem is after warmup, dont clogged cats usually reveal themselves after they get hot? Thanks for the advice guys ill let you know what i figure out.

 

[PalmettoFJ62]

You might also check for air leaks somewhere on the intake side.

Good luck,

The accordian shape tube on the intake was rotted and was just recently replaced as well as the intake manifold gasket. I thought these fixed my problem for sure. It does run much better now but didnt fix the main problem.

 

[waiting for time]

What happends when you stop and let it cool down for 1 to 2 minutes, 5 to 10 minutes, and for 30 to 45 minutes?

If it is heat related this will give you an idea how close it is to the engine.
If it is directly in contact with the engine it will defenitly be there after 1-2 min. because of heat rise after waterpump stops running.
5 to 10 minutes (open hood) engine temp will be arround working temp depending on outside temp but sensors not directly on the engine will be a bit cooler.

It is a primitive way to do a diasnostic but it might give you a bit more indication where to look.

 

[PalmettoFJ62]

What happends when you stop and let it cool down for 1 to 2 minutes, 5 to 10 minutes, and for 30 to 45 minutes?

If it is heat related this will give you an idea how close it is to the engine.
If it is directly in contact with the engine it will defenitly be there after 1-2 min. because of heat rise after waterpump stops running.
5 to 10 minutes (open hood) engine temp will be arround working temp depending on outside temp but sensors not directly on the engine will be a bit cooler.

It is a primitive way to do a diasnostic but it might give you a bit more indication where to look.

Ill have to try this after work today and see if that helps narrow this down a bit.
I did check resistance of the primary and secondary circuits on the coil and the primary read zero ohms which is not in spec. the secondary read within factory spec. Maybe i found my problem but id think that if this were the case it would be causing problems all of the time and not only after being driven a while.

 

[Michael Hanson]

I have found coils get worse as you drive but frequently appear fine at the first start up of the morning. See if napa can test it for you. MIke

 

[waiting for time]

Let the car run warm and messure it again.
may be you get a different reading.
Did the CPU give you any codes?

 

[PalmettoFJ62]

The test on the coil the first time was right after then engine had been running for a while so it was hot. I tried again yesterday afternoon when i got off work and the resistance in primary circuit was .9-1.1, and the secondary was 14.5k so the primary is still not in factory spec. The engine was cold. What would you guys do? Is that enough evidence to replace the coil?

 

[waiting for time]

Warm it up and test a few times at different temps until the engine starts to give the problem.
If it gives the same readings when warming up it I would replace it.

Good luck,

 

[PalmettoFJ62]

Warm it up and test a few times at different temps until the engine starts to give the problem.
If it gives the same readings when warming up it I would replace it.

Good luck,

Did this and still did not read within fsm recommended spec. ordered and replaced with new factory coil as well as new air filter and still have the same problem.

Only after its at operating temp she runs strong untill I stop for more than a 1-2 minutes. When i press the skinny pedal i can floor it and the engine will stumble to about 2000 rpm and blow alot of black smoke. I have to wait about 10 minutes with engine off before i can get going again and make it home.

If anyone has any new advice it would be greatly appreciated. I am also going to post a link to this thread in my local club forum and see if anyone would like free dinner and beer to help me diagnose.

 

[cruiser guy]

Sounds like a mas air flow sensor to me as well. You can try to clean it with mas air flow sensor cleaner but usually it ends up needing replaced.

what if you just ditch it? cant you desmog a 3fe?

 

[PalmettoFJ62]

We have no vehicle inspections or smog bs here in South Carolina so thats an option if feasable.

 

[waiting for time]

It gives me the impression that something starts to deform when hot, still not leaking but when you stop it gets that extra heat that makes it leak false air. After 10 min. it cools enough to close again.

Did you check the airflow meter?