Did I mess something up? (1 Viewer)

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Hey everyone! I recently bought a 1991 Land Cruiser and I'm having some issues. I've looked at a ton of threads on here and have seen things similar to my issues, but I'm not exactly confident that I didn't cause this problem myself

I wanted to start getting the car back into good shape, so the other day I changed the oil and spark plugs. For whatever reason the 80 wouldn't turn over after the maintenance. I fiddled with the spark plug cables and was able to start the car, but then it would die after a short time idling. I thought maybe the new spark plugs were bad so I put the old ones in one at a time. Everytime I got an old spark plug back in the engine seemed to start better.


So where the 80 stands now.. It will turn over and idle at about 300 RPM. I adjusted the throttle control screw and have it idling just below 600RPM (I know that isn't really a fix). When the car is in park the engine accelerates normally. However, in reverse or drive, I can't get the RPMs over 1000 and the 80 won't go anywhere. Also, when I am warming up the engine after I start it the throttle will be unresponsive, then about 10 seconds later the RPMs will increase as I let off the throttle, and then about another 10 seconds later the throttle will act appropriately but only in park.

I have such a weird range of issues that I don't even know where to start. Any advice or pointers in the right direction would be great. Thanks!
 
Joined
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Did you properly gap the new plugs? Are the new plugs the right plugs for your engine? Do the new plugs fit the plug wires well? How old are the old plug wires? It’s possible you broke one moving them around.
 
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Changed spark plugs and thus removed the throttle body intake to the air filter?? It may have a split on the bellows, very hard to see when re-installed, but will allow unmetered air to get in and lots of running/idling issues ensue... As the engine rocks (going from N to D to R etc) the bellow split opens and closes... Anyhow, check very closely and see if that is your problem.

cheers,
george.
 
Joined
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Did you properly gap the new plugs? Are the new plugs the right plugs for your engine? Do the new plugs fit the plug wires well? How old are the old plug wires? It’s possible you broke one moving them around.
I didn't gap them. I'm really new to working on engines. But all of the original plugs are back in except for one new one is still in there and we did gap that one. The plugs seemed to fit just fine. Bought them from AutoZone so they looked up what plugs would work. The plug wires could be old, I have no idea, but I ordered new ones
 
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Changed spark plugs and thus removed the throttle body intake to the air filter?? It may have a split on the bellows, very hard to see when re-installed, but will allow unmetered air to get in and lots of running/idling issues ensue... As the engine rocks (going from N to D to R etc) the bellow split opens and closes... Anyhow, check very closely and see if that is your problem.

cheers,
george.
I didn't have to remove anything to get the plugs out. I've looked over the intake to the airfilter and haven't noticed any cracks. Would it be a noticable hole?
 
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It likely would be a crack/slit in the bellows area of the 'hose'. Very hard to see with the hose in place. If original the hose would be quite brittle with age.

If you moved it around to get at the plugs, the possibility is there that the hose was damaged...

cheers,
george.
 
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There is no "throttle control screw" on this engine. The "golden screw" on the top of the intake will have a temporary effect on idle speed, but the idle speed is controlled by the ECU and ISC valve.
The correct setting for the golden screw is 1/4 to 1/2 turn from fully seated.
 

leonard_nemoy

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1. Take anything @jonheld says about the 3fe as law, he is never wrong.

2. Correct the screws position that Jonheld mentioned.

3. Verify that you are using new OEM spec spark plugs that are correctly gapped.

4. Buy new OEM or OEM spec wires. Spark plugs and wires should almost always be changed together.

5. In line w/#3, change the cap and rotor on your distributor. This should also usually be done at the same time as new plugs and wires.

6. Also as listed earlier check the intake tube inbetween the air filter and throttle body for cracks.

7. Do not open or try to clean the airflow sensor/air meter thing. It is not like a MAF on newer vehicles. Just leave it alone!!!!!

8. Post some pics, and drink some beers.

goodluck
 

spazzyfry123

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Worked fine, changed plugs, now can’t get it to work correctly even with putting in old plugs? Something else is up. Make sure you REALLY have the wires on the plugs. Takes some force.

I also agree with @george_tlc a good chance you may have cracked the tube. Very very easy to snap with age. Not that I know about it first hand or anything…
 
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There is no "throttle control screw" on this engine. The "golden screw" on the top of the intake will have a temporary effect on idle speed, but the idle speed is controlled by the ECU and ISC valve.
The correct setting for the golden screw is 1/4 to 1/2 turn from fully
Okay, yeah. That's what I unscrewed. It had a little effect on idling speed buti know that is not a fix whatsoever.
 
Joined
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1. Take anything @jonheld says about the 3fe as law, he is never wrong.

2. Correct the screws position that Jonheld mentioned.

3. Verify that you are using new OEM spec spark plugs that are correctly gapped.

4. Buy new OEM or OEM spec wires. Spark plugs and wires should almost always be changed together.

5. In line w/#3, change the cap and rotor on your distributor. This should also usually be done at the same time as new plugs and wires.

6. Also as listed earlier check the intake tube inbetween the air filter and throttle body for cracks.

7. Do not open or try to clean the airflow sensor/air meter thing. It is not like a MAF on newer vehicles. Just leave it alone!!!!!

8. Post some pics, and drink some beers.

goodluck
Thanks! I have already ordered new plug wires, cap, and rotor. Just waiting on them! I'll definitely follow this list.
 
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Thanks for all the replies and help guys. So I'm going to go ahead and replace the intake hoses and get the new plug wires, distro cap, and rotor and I'll report back
 

mudgudgeon

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Thanks for all the replies and help guys. So I'm going to go ahead and replace the intake hoses and get the new plug wires, distro cap, and rotor and I'll report back

You can temporarily patch the intake hose by tightly and neatly wrapping it with PVC duct tape (the type that stretches, not the fabric type).

This might help trouble shoot and eliminate or confirm the hose as a problem
 
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Any unmetered air entering the system will play havoc with the idle/power/fuel delivery.
The top half of this motor wants to be air tight. There's a gasket on the oil fill cap, dipstick, PCV valve, valve cover grommets, etc to keep it tight.
As mentioned earlier, unmetered air is the single most common cause of running issues.
DO NOT REMOVE THE 2 PHILLIPS SCREWS ON THE AIR FLOW METER HOUSING.
There is a thin spring steel clip that gets lifted to remove the connector.
 
Joined
Jun 19, 2021
Messages
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Location
Fort Worth
Any unmetered air entering the system will play havoc with the idle/power/fuel delivery.
The top half of this motor wants to be air tight. There's a gasket on the oil fill cap, dipstick, PCV valve, valve cover grommets, etc to keep it tight.
As mentioned earlier, unmetered air is the single most common cause of running issues.
DO NOT REMOVE THE 2 PHILLIPS SCREWS ON THE AIR FLOW METER HOUSING.
There is a thin spring steel clip that gets lifted to remove the connector.
I ordered the intake hose kit and 3FE tune up kits off of Wit's End. Try to cover all my bases. Thanks.
 

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