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

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

Joined
Sep 10, 2021
Threads
2
Messages
35
Location
Nc
Hope al is well-
I had overheating issues due to the tank on rad cracked, and I'm on the road and have been running my 92 fj80 3fe on empty. A lot. In a desperate last ditch effort to get my family back together.
It over heated pretty bad before this problem and I heard to thuds from the engine while trying to start it.
It has a little fuel. When I try and start it, i therea orange spark out the spark plug wire as its rested on the valve cover. No cel on dash in on position. I've wedged a piece of bark on the fpr while trying to crank and getting a jump. It cranks, and wants to start, but I thought why not bypass the fusible link and so I have those 3 wire now directly to the positive. Still no cel on on.
Efi relay looks brand new.
Could it simply be the ecu just isnt getting power? I have no test light just hand tools.
Sincerely,
Lost

P.s. I know I'm gonna get s*** for bypassing the fuseable link but it was a last ditch effort.
 
Hope al is well-
I had overheating issues due to the tank on rad cracked, and I'm on the road and have been running my 92 fj80 3fe on empty. A lot. In a desperate last ditch effort to get my family back together.
It over heated pretty bad before this problem and I heard to thuds from the engine while trying to start it.
It has a little fuel. When I try and start it, i therea orange spark out the spark plug wire as its rested on the valve cover. No cel on dash in on position. I've wedged a piece of bark on the fpr while trying to crank and getting a jump. It cranks, and wants to start, but I thought why not bypass the fusible link and so I have those 3 wire now directly to the positive. Still no cel on on.
Efi relay looks brand new.
Could it simply be the ecu just isnt getting power? I have no test light just hand tools.
Sincerely,
Lost

P.s. I know I'm gonna get s*** for bypassing the fuseable link but it was a last ditch effort.

FB_IMG_1642393292135.jpg
 
92 fj80 3fe egr delete smog delete cat delete ran awesome for 3 years before this problem as my mudding truck. The clunk I felt could have been the timing chain jumping and timing is off now? Idk. I gotta get my head straight on this one. Many variables. I need an adult.

20211214_140212.jpg
 
3FE uses gears for timing - no chain, no belt...

cheers,
george.
 
3FE uses gears for timing - no chain, no belt...

cheers,
george.
If no cel in on position, and literally bypassed the fuseable link, what next you think? And yes cheers. I just got myself a nap with the pup a brew and gonna go back at it in a parking lot 😂
 

download and read - 3fe specific.

@jonheld may be able to help once you've gone through some of the stuff in the above doc.

cheers & good luck,
george.
 
It would make sense that running the truck hot af could have damaged the power wire to ecu being it's so close to the exhaust manifold.
I do have a question though. I just hard wired/bypassed the fuseable link. Could that be a problem during this diagnostic until I find a new fuseable link?
What you sent me is actually making sense. I'll keep you posted God Speed and I really appreciate you much luv-



Mikey and Kado
 
You can make a test light. Find the smallest lightbulb and socket you can in the truck that works and you can take it out, including the socket. Cut it out of the harness, leave enough room to splice it back. Try to find a bulb that has other bulbs like it in the truck that you can get to in case you short it out and burn up your bulb. Don't use this as a jumper wire, it's just to find juice. Jumper wires can be speaker wire, wires from a smog solenoid, tail light, turn signal, horn wire etc.

Turn signal bulbs and tail light bulbs draw quite a bit of juice and may damage ECM components but they will work to test primary feeds, fuses etc. Add wire from something you can live without, like a speaker, to get test leads long enough you can use. Insulate splices if you can, so you don't short them out on fenders etc. Paperclips, screws, soda can tabs, all work to make ends for the wires you can use to probe and test with.

Start with the power to things that make the CEL work. From that list, I pasted the things that you can do without an OHM meter. My apologies if this violates some protocol but the cause is worthy.


Diagnostic Procedure for 1991/1992 3F-E EFI Related Issues

Motor not running; key in ON position;CEL, A/T, CHARGE lamps should be on. No CEL=No StartThe EFI circuit is initiated from the ECU (E5-pin 3) which energizes the EFI relay coil. The load side of the EFI relay feeds +12 to the ECU (EFI on logic), all 3 VSV valves, both O2 sensors, the ISC valve, pin 8 (B+) on the DIAGNOSTIC connector, and the load side of the circuit opening relaywhich feeds the fuel pump.

All EFI related +12 comes from the 15 amp EFI fuse in the under hood fuse box. This fuse also feeds constant B+ to the ECU. The CEL (CHECK ENGINE LIGHT) is illuminated by the ECU with a logic low on E6-pin 8 and should alwaysfunction as described. In other words... No CEL=No Start.

The most common cause of a no-start is a failed fusible link, Toyota part# 90982-08264Below is a cursory check of all 3 fusible links in system. This assumes an unmolested OEM configuration.

FL AM1-Dome lights working?
FL AM2-When you turn the key to ON does the CHARGE LAMP light up?
FL MAIN-Brake lights working?

If yes to all 3, then all 3 fusible links are intact.

* A short or damage inside the AFM can cause the CEL not to illuminate. A short or damage is usually the result of removing the 2 Phillips screws on the connector housing when trying to remove the connector. Do not remove the screws.There is a thin spring steel clip that you just need to push up. A quick AFM diagnosis is to simply unplug the AFM connector. If the CEL now illuminates, the problem is internal to the AFM.

* Proper operation of the AFM will shut down the fuel pump when the air flow flap closes. This ensures that in the event of an accident/motor stall the fuel pump is not running even with the key in the ON position. There have been several reports of folks being able to unplug the AFM connector and the truck continuing to run. THIS IS WRONG AND POTENTIALLY LETHAL. Look into the CIRCUIT OPENING RELAY in the left kick panel and test associated fuel pump logic. Motor not running; key in ON position; CEL, A/T, CHARGE lamps should be on. If ALL 3 are out, check IGN fuse and fusible link AM2 or ignition switch.

"Motor not running; key in ON position;CEL, A/T, CHARGE lamps should be on. If no CEL then,

* Check for +12 VDC on brass terminal screw in under hood fuse box. This terminal is located directly to the left of the main fuse and is a Phillips screw head.
* If no +12 VDC in fuse box, then check fusible links off positive battery terminal. 2 to the black plastic junction box and one to the connector.
* If +12 VDC in fuse box and no CEL, then suspect EFI relay/fuse and associated wiring and contacts. Many have said that the wire from the EFI fuse to the EFI relay is undersized and is the root cause of all these problems. I disagree with this. At 2500 RPM I measured 6.25 amps across the load side of the EFI relay contacts. I believe the cause of the problem is related to the heat of the manifold combined with poor crimps on the connectors in the fuse box. Over time these connectors can become corroded and resistive.
* Check for +12 on pin 8 (B+) on the DIAGNOSTIC connector mounted on the right side of the fire wall. If +12 on pin 8 and still no CEL, then EFI circuit OK and problem is with ECU or related wiring."

Coil/Igniter:The coil/igniter are mounted as a pair on the right front fender next to the cruise control actuator. If CEL is ON and no spark from coil, then possible coil/igniter failure. In the FSM there is no diagnostic procedure for the igniter. These can become intermittent and the only course of action is to swap it out with a known good one. Both the ignition coil and igniter are grounded through the mounting bracket. It must be secured to the body.Distributor coils can open or short but are not a common failure. Be certain that the distributor pickup coils are hitting the ECU. G (E4-pin 18) NE (E4-pin 4) G-(E4-pin 17)

Some notes on fuel pump operation:

The fuel pump is fired by the CIRCUIT OPENING RELAY and its 2 logic paths, left side kick panel, bottom center below the relay block.

The primary relay coil is energized from the STARTER circuit when cranking the starter.

The secondary relay coil is energized when the flap in the AFM opens after the motor starts sucking air.

For diagnostic purposes only,you can bypass all fuel pump logicby shorting pins 1 (FP) and 8 (B+) in the diagnostic connector mounted on the firewall. This will force the fuel pump to run with the key in the ON position, assuming proper operation of the EFI circuitry.

PINOUT of DIAGNOSTIC CONNECTOR:

Firewall side of Diagnostic Connector

IG(18)
Cover Hinge Side: TT(17) / TS(16) / OX2(11) / VF2(10) / VF1(9) / B+(8)
TC(15) / CC2(14) / BLANK / TE2(7) / TE1(6) / CCO(5)
OPT(13) / AB(12) / OX1(4) / E1(3) / W(2) / FP(1)

The diagnostic pins are hard to access. A paperclip works but it's hard to make a good connection. Best is a blade connector from a crimp on type wire connector, you cut it roughly in half so the blade part is only 1/2 as wide as normal. That allows you to make a good connection. In a pinch, you could probably bend the end of the keyring straight and use that to probe the connections and attach that to your home made jumper-wire.

If you are too low on fuel, it will pump air bubbles into the lines. Bubbly fuel won't work an injector. You can compress it as long as the pump is on but when the injector opens, all it shoots in is compressed air and a tiny bit of fuel. The fuel pump itself is under the rear seat if I remember right. You should be able to hear it running when you do the jumper wire trick in the connector to bypass the circuits and turn on the pump. If you can't hear the pump run, it might be dead. Sometimes you can get them to work by banging on the bottom of the tank hard or the lid where the pump drops down into the tank while the wire is hooked up. If it starts running after you did that, you have a bad armature in the pump. As soon as you take the juice off that pump, it's going to stop and probably stick again in the same spot. The same trick may not work twice to get that pump to run.

The pinout gets fubar'd when I post the thread. You'll figure it out if you use that guide he provided above and correspond it to what I typed.
 
Stop thinking "could have would have". Dont start thinking it was the timing belt unless you have a reason to think that. If you really over heated it then yes you could have kille dit. But that would usually be HG, cracked head or seaized it. Coolant in oil and oil in coolant will often tell you if it is a HG, it will also often still start with a bad HG. If it was seized it should not turn over. So look at the simpler stuff. It ran and then it didnt. Two rules. Start with the basics. Do you have spark, do you have fuel.

Then look at the last thing you messed with if anything before it stopped running. If you had your hands under the hood messing in a area look there. You might have just bumped a bad connector or pinched a wire.

As always i am not trying to be a dick even though i sound like one. Take a deep breath, drink a bear if you need to and go from there. You probably need a basic multi meter or test light. but other than that you can pull a spark plug and see if you have spark. If it will crank a good while spin it over then pull another plug and see if it is wet from fuel. This is my uneducated approach.

Diagnostics are hard and i am not great with it. Start with the basics and simple stuff.

I am in NC, if i was closser i would come on out and try to hel, but i am all the way west. Good luck and hang in there.

I think there is a pretty active NC group in the club house. I would also post a RTH request and see if they can help you out. I dont know crap about the 3FE so i dont have much to offer. Good luck!
 
It is hard to kill a 3FE. So unless you want a new engine, why would you keep driving it knowing the radiator was cracked??? How bad did you overheat the engine? was the needle all the way at the top?
 
Not to pile on here, but damn, those "may pop" tires on the front are straight sketchy.
That pic I posted was a month ago.
These are brand new 285 75 r16s MTS all around. Coopers in back iron man up front. They are amazing offroad I run 33psi on the street I run 65 front 70 rear
16449482391894204218511093066078.jpg

Not to pile on here, but damn, those "may pop" tires on the front are straight sketchy.
 
It is hard to kill a 3FE. So unless you want a new engine, why would you keep driving it knowing the radiator was cracked??? How bad did you overheat the engine? was the needle all the way at the top?
Because when the wp belt snapped, it severed the coolant temp sensor wire without my knowledge. I had thought I ran over something.
So driving, the coolant temp on dash was giving me the ambient temp of the engine bay. And the tank on the rad thankfully was the weakest link. Make more sense?
 
Last edited:
Stop thinking "could have would have". Dont start thinking it was the timing belt unless you have a reason to think that. If you really over heated it then yes you could have kille dit. But that would usually be HG, cracked head or seaized it. Coolant in oil and oil in coolant will often tell you if it is a HG, it will also often still start with a bad HG. If it was seized it should not turn over. So look at the simpler stuff. It ran and then it didnt. Two rules. Start with the basics. Do you have spark, do you have fuel.

Then look at the last thing you messed with if anything before it stopped running. If you had your hands under the hood messing in a area look there. You might have just bumped a bad connector or pinched a wire.

As always i am not trying to be a dick even though i sound like one. Take a deep breath, drink a bear if you need to and go from there. You probably need a basic multi meter or test light. but other than that you can pull a spark plug and see if you have spark. If it will crank a good while spin it over then pull another plug and see if it is wet from fuel. This is my uneducated approach.

Diagnostics are hard and i am not great with it. Start with the basics and simple stuff.

I am in NC, if i was closser i would come on out and try to hel, but i am all the way west. Good luck and hang in there.

I think there is a pretty active NC group in the club house. I would also post a RTH request and see if they can help you out. I dont know crap about the 3FE so i dont have much to offer. Good luck!
Your not being a dick. That makes sense. To put this in to context- I'm dealing with a lot and thus said **** it. But you are right. That's what I need to do. Get my head right first and then go about it with a level head. No milky oil when checking dipstick tho. But that's not to say I didnt blow it. I just hit 251,000
 
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?
 

Users who are viewing this thread

Back
Top Bottom