Real time help (1 Viewer)

[cruiserdan]

We have a 97 80 that is dead on the trail and we are running out of daylight.


It will start and run for ~a minute and then dies and it loses head lights and dash lights at the same time. It then cures it's self and repeats the process.


So far swapped EFI relay, fuel pump relay, headlamp relay and bypassed fuse links.

14 volts at battery when engine does run.
any ideas?


help!

D-

 

[flintknapper]

Might try disconnecting the battery and intermitting it several times. Might reset something.

Sounds like you're on the right track though, relay of some sort....or some other fail safe feature.

 

[cruiserdan]

No-go. The battery has been disconnected multiple times.

 

[flintknapper]

Looked carefully at all engine wiring harness' for burn throughs (shorts).

I have an EWD in my shop Dan and can stay with you answering any questions, but I am not as savvy as the other folks here on troubleshooting these things (mine never breaks). I'll do what I can for you.

 

[Firedog]

Try swapping a battery or running jumper cables from another truck?Possibly a ground problem? Try running jumper cable as a second ground.

 

[RockDoc]

Does it restart immediately, or does it need to cool down first? Some sort of heat related wiring or sensor fault?

 

[gray]

Pure guess; does it have an alarm system (ie: shutting things down)? That wouldn't explain losing the lights though; a head scratcher; why a complete intermittant power loss? Can you disconnect the MAF and see if it stays running (default limp home mode)??

 

[flintknapper]

Do you have an OB reader/scanner with you?

 

[landtank]

all I got for you Dan is possibly the battery. My buddy had a battery with an internal break in it and it would behave weird at times.

 

[medtro]

Headlights wires go through MAIN fusible link, and you bypassed that already. I would swap igniter and coil next, this is just a guess based on the spare parts I have in my truck.

 

[cruiserdan]

Looked carefully at all engine wiring harness' for burn throughs (shorts).



I have an EWD in my shop Dan and can stay with you answering any questions, but I am not as savvy as the other folks here on troubleshooting these things (mine never breaks). I'll do what I can for you.

Possibility. Recent head gasket replacement. Maybe something got jacked.


There is an EWD and FSM on-site with the team. Beowulf, Ali, Pappy and Beno are all there.

Try swapping a battery or running jumper cables from another truck?Possibly a ground problem? Try running jumper cable as a second ground.

It's had at least 4 different batteries in the last ~24 hours.

Does it restart immediately, or does it need to cool down first? Some sort of heat related wiring or sensor fault?

It will re-start after a few minutes.

Do you have an OB reader/scanner with you?

I don't think they have one.

Headlights wires go through MAIN fusible link, and you bypassed that already. I would swap igniter and coil next, this is just a guess based on the spare parts I have in my truck.

I dont know if they have those. I think that the loss of the headlights is a major clue but I'll be damned if I can figure it out.


One more bit of info: when the vehicle first konked out it was displaying a charge-lamp. They did discover and repair a bad connection at the alternator and when the engine does run it's putting out ~14 volts.

 

[RockDoc]

Have they tried swapping the battery (internal short?) or running purely on the battery to by-pass any alternator problems? (although the fuse links should go if if is a short in the Alt wiring)

EDIT Whoops, just saw they have swapped batteries. Nix that.

 

[LandCruiserPhil]

Possibility. Recent head gasket replacement. Maybe something got jacked.


SNIP


It will re-start after a few minutes.


I dont know if they have those. I think that the lose of the headlights is a major clue but I'll be damned if I can figure it out.


One more bit of info: when the vehicle first konked out it was displaying a charge-lamp. They did discover and repair a bad connection at the alternator and when the engine does run it's putting out ~14 volts.

I would be looking for a grounding problem on the body side with all the above info.
You have 2 sources producing 12V on the postive side

 

[cruiserdan]

I would be looking for a grounding problem on the body side with all the above info.

Good suggestion, I'll forward that.

 

[FirstToy]

Dan,
that sounds a lot like Doug's situation at DV. It was the actual fuel pump, removed thru the 2nd row seat port. The wire was frayed and shorted. Possible?

good luck

 

[cruiserdan]

I wondered about that but did Doug lose his lights when the engine quit?

 

[turbocruiser]

Dan, sorry I saw this so late, but, several thoughts in the hope it helps:

1. Intermittent RPM signal - IIRC all Toyota fuel pump circuits include a safety shutoff switch whenever the vehicle loses its RPM signal (not the tach on the dash but the ECM's signal).

2. Fuel pump failure - it spins long enough to start then shuts off ... OR ... fuel pump filter clog - it allows some startup fuel through the system but then not enough to run ... OR ... that wire to the pump that tends to fray (someone here had that recently.)

3. Broken wire within MAF sensor - can you swap another one and see if it fixes the problem just for now? If so perhaps you can get the rest of rigs to the end of the trail and grab someone's MAF and go back with only one rig to rescue the other?

I'd look at the first thing above - if someone has scanner see if the RPM that the ECM gets matches the tach on the dash. I really hope this helps.

 

[nspctr1]

Dan,
that sounds a lot like Doug's situation at DV. It was the actual fuel pump, removed thru the 2nd row seat port. The wire was frayed and shorted. Possible?

good luck

X2 on the fuel pump. good luck....

 

[FirstToy]

Dan, I forgot the details on that. I do know they changed every fuse and tore into the dash...everywhere and it ended up being that frayed wire on the pump itself.
If they crap out on the other stuff, might be worth a look.

dan here's the link
https://forum.ih8mud.com/showthread.php?t=84774&page=5

 

[RockDoc]

Just a shot in the dark, but could the fault be in the ignition switch/column wiring?