Need help with motor diagnosis.

[Wabi-Sabi-FJ60]

To Anyone who can help,

My name is Alex and I own a 1985 Toyota Land Cruiser FJ60 with a stock 2F motor with a factory 5 speed transmission with @192K miles. I absolutely love this vehicle and have taken her on some local camping trips with my family in the hopes of even more trips in the future. I purchased her in March of 2019 and ran flawlessly up until recently (within the last few months) she began to show some signs of something going south. First were the hard starts where I would start her up, then the brake and seatbelt lights would intermittently flash all the while I was keeping the engine running by feathering the gas pedal, then after about 30 seconds to a minute, suddenly the lights would stop flashing and then she would idle fine. This would happen no matter if it was the first start in the morning or whether the motor was warmed up. She also started to have more of a pronounced exhaust leak. I recently had the exhaust leak fixed and had all the vacuum hoses replaced. She ran flawlessly from where I picked her up in San Jose, to my home in Hayward, CA. The next morning, I started her up and she would do her hard start again with the brake light and seatbelt lights flickering until after a few seconds they would stop flickering and then she would idle fine. I decided to run an errand to Target then as I drove into the parking lot, that's when she lost power and stalled out. I managed to get her started and then she seemed to run pretty rough to where she would lurch in first and second pretty violently like she was running out of gas. I had filled her tank up the day before.

My gut is telling me it has something to do with the carburetor. Not being a mechanic myself, it is merely a guess on my part. I have been dealing with this for the past few months now and have gotten to the point where I don't feel confident enough driving her much less with my family. I don't want to give up on her just yet as I feel like it could be something as easy as a rebuilt carb, but again, this is only a guess on my part.

I am reaching out to anyone who knows of a mechanic that specializes in these vehicles and may know what is wrong based on my descriptions (I realize this is a long shot on my part) or knows how to rebuild these carburetors. I am hoping that someone has gone through the same predicament and could offer up some answers or at the very least point me in the right direction to get some help.

I hope this finds everyone healthy and safe during these very weird times!

Thanks in advance on any help.

best regards,
-Alex

 

[M Rose]

Alex, I think what you describe is more inline with a ignition control module going bad, or a bad contacts on the ICM. I wish I could tell you how to diagnose this problem, but I don’t know what voltages should be present at the ICM and the ignition coil secondary windings.

 

[Wabi-Sabi-FJ60]

Hello TexasGMG,

Thanks for reaching out. I will look into those for sure. At least it gives me something to focus in on. I have been looking at it as a whole and it can become overwhelming. This might be what I need!

hope this finds you well and stay healthy out there!
Best,
- Alex

 

[ChasingOurTrunks]

Is the flashing lights steady, like a programmed warning? Or are they intermittently flickering, as if they are getting inconsistent power/signals?

Any chance of contamination in the fuel? How many tanks have you run through since the problems first started?

I can't speak to all the symptoms, but it sounds like a fuel and/or ignition issue as M Rose said. Here's my thinking:

1) The easiest thing to do is to treat the fuel with SeaFoam or some other fuel treatment specifically designed to get water out.
2) The truck is as old as I am -- my own filters get worse with age. When was the lsat time the fuel filter was changed on this rig? Parts of your description sound like it's starving for fuel, so if there's a plugged filter somewhere that might be why. If the throttle control knows to be say 15% open to idle the vehicle, but there's a reduction of even 1% in your filter flow and the vehicle cannot compensate (which would not surprise me given it's age), it might not idle well. The slow decay of the performance over time makes me wonder about this being a possible explanation. It could also be the pump; some rigs have integrated pump and filter, others are separate.
3) If that doesn't sort it out, then check the trickier parts of the fuel system -- clean the carbs and make sure they are allowing the right fuel and air mix in.
4) I would only then start to check electrical, personally, including the ignition system. The fuel system is pretty easy -- if it's clean, it'll work, so that's why I suggest starting there. The electrical system starts getting more complex as you can get into resistance, circuits, wiring diagrams, etc. All easy enough to do in practice, but it's a bit of a steeper learning curve.

Those are my observations but again, I stress that I have zero experience with that platform and the above is very general thoughts based only on your post.

 

[Jostr]

It's pretty hard to diagnose a problem without seeing/hearing it but... if it's fuel related a good test to run on a carb engine is to give it an external shot of fuel. ie brake cleaner/ carb cleaner after you first start it and it's running ruff. If it clears up then you know it's a fuel delivery issue. The flashing lights could be a bad loose ground, but most likely because the engine hasn't ran the alternator fast enough to start charging.

Just a starting point.. I'll keep checking back for updates

 

[Boostpowered]

Sounds electrical to me with the lights flashing. Bad ground? Alternator going out? Personally I vote bad ground, check all the spots where something electronic grounds to the body and frame also look for frayed or exposed wires on the power side it could be shorting out too.

 

[Wabi-Sabi-FJ60]

Is the flashing lights steady, like a programmed warning? Or are they intermittently flickering, as if they are getting inconsistent power/signals?

Any chance of contamination in the fuel? How many tanks have you run through since the problems first started?

I can't speak to all the symptoms, but it sounds like a fuel and/or ignition issue as M Rose said. Here's my thinking:

1) The easiest thing to do is to treat the fuel with SeaFoam or some other fuel treatment specifically designed to get water out.
2) The truck is as old as I am -- my own filters get worse with age. When was the lsat time the fuel filter was changed on this rig? Parts of your description sound like it's starving for fuel, so if there's a plugged filter somewhere that might be why. If the throttle control knows to be say 15% open to idle the vehicle, but there's a reduction of even 1% in your filter flow and the vehicle cannot compensate (which would not surprise me given it's age), it might not idle well. The slow decay of the performance over time makes me wonder about this being a possible explanation. It could also be the pump; some rigs have integrated pump and filter, others are separate.
3) If that doesn't sort it out, then check the trickier parts of the fuel system -- clean the carbs and make sure they are allowing the right fuel and air mix in.
4) I would only then start to check electrical, personally, including the ignition system. The fuel system is pretty easy -- if it's clean, it'll work, so that's why I suggest starting there. The electrical system starts getting more complex as you can get into resistance, circuits, wiring diagrams, etc. All easy enough to do in practice, but it's a bit of a steeper learning curve.

Those are my observations but again, I stress that I have zero experience with that platform and the above is very general thoughts based only on your post.

Hello COT,

I have recently replaced my Fuel filter (within the last 2 months). Will definitly do the easiest to fix to the hardest I'll run some SeaFoam as I have a can of that readily available. One the weather permits, I will run through all the fuel lines and make sure they are all flowing freely.

Will keep you updated as I progress!

BTW, I hear different takes on the fuel filler cap whether it need so be ventilated or not. As it is currently, when I take the fuel cap off, I usually hear a "pressure" release. Not sure if its a sucking sound or pressure being released.

Thanks again!
-Alex

 

[Wabi-Sabi-FJ60]

It's pretty hard to diagnose a problem without seeing/hearing it but... if it's fuel related a good test to run on a carb engine is to give it an external shot of fuel. ie brake cleaner/ carb cleaner after you first start it and it's running ruff. If it clears up then you know it's a fuel delivery issue. The flashing lights could be a bad loose ground, but most likely because the engine hasn't ran the alternator fast enough to start charging.

Just a starting point.. I'll keep checking back for updates

Hello Boostpowered,

My thoughts exactly. Like I mentioned, the flickering seatbelt light might be a hint of something not grounded properly and be completely coincidental to when it stops flickering to when the motor begins to idle properly. I'll try and add a video if I can catch it when happens.

best,
-Alex

 

[Wabi-Sabi-FJ60]

It's pretty hard to diagnose a problem without seeing/hearing it but... if it's fuel related a good test to run on a carb engine is to give it an external shot of fuel. ie brake cleaner/ carb cleaner after you first start it and it's running ruff. If it clears up then you know it's a fuel delivery issue. The flashing lights could be a bad loose ground, but most likely because the engine hasn't ran the alternator fast enough to start charging.

Just a starting point.. I'll keep checking back for updates

Hello Jostr,

I agree. Its hard to diagnose without someone here to see and hear it realtime. I am trying to take a video of it happening and will upload to hopefully get a clearer description of what's happening. Do you happen to know where the seat belt sensor is located? Its been raining here and I haven't had a chance to tear into my B-piller to find it. I've tried to look online, but can't seem to find it.

Anyways, I really appreciate everyone who has offered their help! Hope everyone is home safe and sound!

best,
-Alex

 

[Boostpowered]

Hello COT,

I have recently replaced my Fuel filter (within the last 2 months). Will definitly do the easiest to fix to the hardest I'll run some SeaFoam as I have a can of that readily available. One the weather permits, I will run through all the fuel lines and make sure they are all flowing freely.

Will keep you updated as I progress!

BTW, I hear different takes on the fuel filler cap whether it need so be ventilated or not. As it is currently, when I take the fuel cap off, I usually hear a "pressure" release. Not sure if its a sucking sound or pressure being released.

Thanks again!
-Alex

Its good to have vented caps if your tank dont have a vent but its not normally neccisary for function of carbeurated engines. The hiss is pressure built up from the gas vapor . If you roll over without a vent and dont cut off the engine you could get vapor lock but thats not nearly as big a deal as rolling the vehicle.

My chevy buggy has no vent and i get that hiss everytime i open the fuel cell to put fuel in

 

[Boostpowered]

Hello Jostr,

I agree. Its hard to diagnose without someone here to see and hear it realtime. I am trying to take a video of it happening and will upload to hopefully get a clearer description of what's happening. Do you happen to know where the seat belt sensor is located? Its been raining here and I haven't had a chance to tear into my B-piller to find it. I've tried to look online, but can't seem to find it.

Anyways, I really appreciate everyone who has offered their help! Hope everyone is home safe and sound!

best,
-Alex

If you have a seatbelt sensor like the ones that tell you you not buckled up its likely in the latch where u buckle/unbuckle. If its a sensor for when you wreck the it would be in the b pillar.

 

[Wabi-Sabi-FJ60]

Hello All,

I managed to make a video of what happens when I start her. This happens whether the car is warmed up or cold. This video is when she is warmed up already. I hope there is something in the video that is glaringly obvious to someone out there!

Actually, I have been having difficulty uploading here, but I could email if anyone is interested in seeing. Unless someone knows of how to upload a video here.

 

[Wabi-Sabi-FJ60]

Ok...managed to upload the video!

 

[ChasingOurTrunks]

Ok...managed to upload the video!

Very interesting. Now, this may seem like a dumb suggestion, but some older vehicles had a secondary purpose for a light -- for instance, a solid light means one thing, a blinking light means something totally different. Have you checked to see if the seatbelt light is meant to do that flash on and off for diagnostics? The user manual would probably have info.

If it's not that, it certainly sounds like an ignition issue from the video, but alas I don't know enough about the ignition system of that rig to be of much help. But, those are legendarily fixable, so I'm sure someone has a solution for you somewhere!

 

[Wabi-Sabi-FJ60]

I have Heard of that before as well. Lights that come on and off in a given pattern. But this light is so random in its flickering that it just seems so odd...like a lose ground or something like that. I will look into the ignition and see where that takes me.