Fj80 is my home. Stranded tired broke (1 Viewer)

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With confirmation my new battery is dead and wouldn't accept a charge, and im about to put a new battery in here- is me deleting the fuseable link going to be an issue in diagnosis if it doesn't just start up?
It shouldn't. When the fusible link is working, it behaves just like any other wire. If too much current passes through it, the fusible part melts and the conductor separates, breaking the connection and stopping the flow of electricity.

But as you probably know, if you have an over-current situation and have removed the "fuse," something else is going to melt or burn and that something will allow a lot more current through, which could start a fire.
 
New battery in. Fusable link bypassed. ( I'll replace it asap)
But NO CEL still in on poistion
 
New battery in. Fusable link bypassed. ( I'll replace it asap)
But NO CEL still in on poistion
You can test the fusible link just like any other fuse. If it test good, you should reinstall it before going any further. I'm assuming it is fine as bypassing it did not change the the issue and you didn't mention magic smoke being released. what have you done from the diag list that was posted?
 
@jonheld can confirm, but if you broke the wiring on the coolant temp sensor, the engine needs that sensor signal to run the fuel pump. That would be why you're not getting a CEL with key on.

Don't bypass the fusible links if it has made no change. Put them back in. They are there to keep your truck from burning to the ground.

If the battery is dead, why not recharge it? You seem to be wanting to shoot the parts cannon at the truck instead of actually diagnosing the issue.

Do you have spark? Pull a plug wire and check it. If yes, then move on to fuel system.

Do you have fuel pressure? Check the Schrader valve or crack the line on the injector rail to see if pressure squirts out. The fuel pump on these will NOT run unless the engine is CRANKING or the COR is bypassed and shorted properly.

Stop creating problems by taking apart stuff that is not part of this.

If the belts broke and wrecked stuff, look to figure out everything it wrecked. Did the water pump seize to cause the belts to break and overheat? Did it actually overheat or did the wire break off and then the gauge registered hot?

The CEL will not come on if the ECU doesn't have the correct information given to it. It does NOT mean it doesn't have power. The CEL will only come on if the ECU is satisfied everything is in place to start. That means it can receive signal from sensors as well as power to it.

The 3FE does not typically have head gasket issues.

If you broke the wire on the coolant sensor, it's NOT reading the ambient temperature of the engine compartment. I would start here because that would make it so the fuel pump won't run.
 
@jonheld can confirm, but if you broke the wiring on the coolant temp sensor, the engine needs that sensor signal to run the fuel pump.
I'm going to have to say no to that one. On a 3FE the only things that run the fuel pump are the 2 logic sides of the circuit opening relay.
Primary logic is from the starter circuit.
Secondary logic is from the flap in the air flow meter.
There is no other logic or sensor involved in running the fuel pump.

The coolant temp sensor on the thermostat housing feeds the ECU, and an open or short in that sensor would throw a code 22. I assume the OP has checked for codes???
 
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I'm going to have to say no to that one. On a 3FE the only thing that runs the fuel pump is the 2 logic sides of the circuit opening relay.
Primary logic is from the starter circuit.
Secondary logic is from the flap in the air flow meter.
There is no other logic or sensor involved in running the fuel pump.

The coolant temp sensor on the thermostat housing feeds the ECU, and an open or short in that sensor would throw a code 22. I assume the OP has checked for codes???
Thanks for the clarification Jon!
 
Still stranded. Question: even if there's something major mechcacally going on with the engine, like head gasket, bent valve, whatever...with the key in the on position- the cel should still come on arming the efi correct?
 
I'm going to have to say no to that one. On a 3FE the only thing that runs the fuel pump is the 2 logic sides of the circuit opening relay.
Primary logic is from the starter circuit.
Secondary logic is from the flap in the air flow meter.
There is no other logic or sensor involved in running the fuel pump.

The coolant temp sensor on the thermostat housing feeds the ECU, and an open or short in that sensor would throw a code 22. I assume the OP has checked for codes???
So the coolant temp sensor broke in half. The nut is still on there, but the plastic part of the sensor with the 2 prongs is just hanging there, still plugged into the clip. I attempted to simply glue it on there but wasn't keeping together. Could this be an issue? Obviously I simply need a new coolant temp sensor, but never crossed my mind that could be the issue with it not starting
 
In an earlier post you mentioned that you bypassed the fusible link for some reason. There are 3 fusible links off the positive battery terminal. Did you bypass all 3? Did you test your bypasses?
Have you checked for error codes?
 
I've not checked for error codes. I had to take some self care time and I'm gonna go back at it tonight. But it is confirmed I have a blown head gasket . Can anyone message me? I can handle the head gasket job no problem- but would appreciate some tips on diagnosing what else could be wrong ie timing jump/ what is a good advanced timing on 3fe with 250,000, etc etc. I have nothing but time at this point in my life, and taxes are coming in soon so I'm going to rebuild like..everything.
 
You need a copy of the Factory Service Manual, it has all the answers.
Yes sir where can I download one of those?
And can a water pump gasket failure on 3fe cause no compression ? Can a seized wp pulley not allow it to start? And I still dont have a cel in on position- efi relay good fuse box under hood 12 v fuel pump relay good. Fuel pump not pumping in on position.
 
Yes sir where can I download one of those?
And can a water pump gasket failure on 3fe cause no compression ? Can a seized wp pulley not allow it to start? And I still dont have a cel in on position- efi relay good fuse box under hood 12 v fuel pump relay good. Fuel pump not pumping in on position.

You can download a copy from somewhere here on MUD.

Maybe it's time to sell this 80 and buy something that runs.
 
Yes sir where can I download one of those?
And can a water pump gasket failure on 3fe cause no compression ? Can a seized wp pulley not allow it to start? And I still dont have a cel in on position- efi relay good fuse box under hood 12 v fuel pump relay good. Fuel pump not pumping in on position.
As previously mentioned, the fuel pump WILL NOT RUN with the key in the ON position.
The fuel pump is fired from the 2 logic coils of the circuit opening relay. The primary coil is fired from the starter circuit when cranking the starter. The secondary coil is fired when the flap in the air flow meter opens after the motor starts sucking air.
This is detailed in the 3FE EFI troubleshooting guide that you already have.

If you wish to purchase a complete 1991 Toyota FSM and EWD along with a host of other tasty tidbits, simply click the link in my signature.
 
You can download a copy from somewhere here on MUD.

Maybe it's time to sell this 80 and buy something that runs.
Dude this thing was running absolutely amazing before the water pump belt snapped, severed the coolant temp sensor and I drove it hot for just a bit. You either have no drive, or your tryin buy it yourself. Or you dont have kids, or your a rich kid, or your not German. If I gotta rebuild it I'll rebuild it. I've never tried to fix something and failed in my 38 years on this planet. Except relationships with women. That's the s*** that keeps me up at night. Lol. Trust when I say I'll have her up and running here soon.
 
@jonheld can confirm, but if you broke the wiring on the coolant temp sensor, the engine needs that sensor signal to run the fuel pump. That would be why you're not getting a CEL with key on.

Don't bypass the fusible links if it has made no change. Put them back in. They are there to keep your truck from burning to the ground.

If the battery is dead, why not recharge it? You seem to be wanting to shoot the parts cannon at the truck instead of actually diagnosing the issue.

Do you have spark? Pull a plug wire and check it. If yes, then move on to fuel system.

Do you have fuel pressure? Check the Schrader valve or crack the line on the injector rail to see if pressure squirts out. The fuel pump on these will NOT run unless the engine is CRANKING or the COR is bypassed and shorted properly.

Stop creating problems by taking apart stuff that is not part of this.

If the belts broke and wrecked stuff, look to figure out everything it wrecked. Did the water pump seize to cause the belts to break and overheat? Did it actually overheat or did the wire break off and then the gauge registered hot?

The CEL will not come on if the ECU doesn't have the correct information given to it. It does NOT mean it doesn't have power. The CEL will only come on if the ECU is satisfied everything is in place to start. That means it can receive signal from sensors as well as power to it.

The 3FE does not typically have head gasket issues.

If you broke the wire on the coolant sensor, it's NOT reading the ambient temperature of the engine compartment. I would start here because that would make it so the fuel pump won't run.
Heard. Your right. And I had to get a new battery because the other one wouodbt accept a charge
 
Dude this thing was running absolutely amazing before the water pump belt snapped, severed the coolant temp sensor and I drove it hot for just a bit. You either have no drive, or your tryin buy it yourself. Or you dont have kids, or your a rich kid, or your not German. If I gotta rebuild it I'll rebuild it. I've never tried to fix something and failed in my 38 years on this planet. Except relationships with women. That's the s*** that keeps me up at night. Lol. Trust when I say I'll have her up and running here soon.
:popcorn:
 
Stop dicking with things you “think” are the issue. If you haven’t taken the time to test with a multi-meter then all your doing is wasting time, burning money and ****ing sh!t up.

People here have already given you advice. Check for spark and check for fuel. If you can’t do that then your best option might be to sell your 80 for something that runs.

Or get a real mechanic out there to figure it out for you.
 
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