Anonymous
Unregistered
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Hi,
I am new to this forum and could use some suggestions( HELP) about solving a fuel injection mystery, the local shop is having difficulties with. Unfortunately the master wiring tech moved recently so it is up to the next in command to find the problem. He is not as good as the tech that left and probably not much better than I am and that is scary. The car belongs to me.
The car is a 87 4 runner 22re. The problem is that two injectors are not firing and both terminals are hot at the injector. As I understand it one should be open ( unless grounded when firing) and the other is always hot? What makes this confusing is that I replaced the injectors first without testing the leads( stupid) and swaped the ecu ( not as stupid) from my other 87 and guess what, still the same problem. It seems the problem lies within the wiring somewhere? I have not had a Toyota loom go haywire in the past and am wondering if we are not overlooking something simple? Before we start testing the whole fi loop, I was wondering if any of you have run into this or have any suggestions? My e mail is jbco@allvantage.com and thanks a lot in advance,
John
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willzrunna96
Body Damage is Cool
Reged: 10/04/04
Posts: 1270
Loc: Long Island, NY
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there are the injector splices to go bad on the 22re im sure people will chime in since i never had this problem but this definelty sound like your problem
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91 pickup 5.29's US GEAR.35x 12.50 trxus m/t.5 speed swap- SOLD!
96 4Runna limited-toytec/OME lift,diff drop Nitto 285/75/16 Elocked=butter
07 FJ cruiser 3" DR coilovers 285/75/16 nitto TG. allpro sliders
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Esquire812
Trail Leader
Reged: 04/25/02
Posts: 5688
Loc: Port Orchard, Washington
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The injectors are wired in pairs on both sides. From the resistor on the passenger inner fender there will be a yellow wire and a blue wire. Yellow for 1 & 3, blue for 2 &4. Similar setup coming off the injectors with a white wire and white/red wire which are the triggering side that lead to pins 10 and 20 of the ECU. Funny thing is, a few inches up from where the #1 injector wiring peels out of the main harness is a butt connector where all 4 triggering wires come together...then on the other side only one of each (1 white and 1 white/red) continue on to the ECU. This buttconnector rots and starts dropping wires. Betchya a nickel thats where your problem lies....especially if the two dead injectors arent paired.
Do a search on here, there have been at least 3 good threads on the subject. Personally whenever doing a rebuild I now include the wiring harness just for this reason. Very common of the 88 and earlier rigs.
~Darin 
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88' 4x4 *22R-EB Gen II*
87' $Runner *22R-EB Gen I*
85' Sillyca 22R-Esq
"I LIVE IN MY OWN WORLD...THEY KNOW ME WELL THERE"
Edited by Esquire812 (02/16/06 01:39 PM)
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Anonymous
Unregistered
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Is this a problem with just the early EFI injector splices (w/resistor pack) or are the later years affected as well?
This is something I can address while I have the transmission out waiting for the replacement.
Does anyone have pics of these splices and location?
Never mind I found something Here  : Some Q's re: injector splices....
Chucky MoMo 
Edited by Chucky_MoMo (02/17/06 01:16 PM)
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Anonymous
Unregistered
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Thanks for the great info. Ill keep you posted.
Darin, you mentioned wire harness when doing rebuilds? Do you replace or just check connections. If replacing where do you find these? Toyota wants as much as the truck is worth.
Thanks, John
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kewlynx
Toyota & Classifieds Moderator
Reged: 10/06/02
Posts: 14038
Loc: Fairbanks, Alaska
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You get rid of those butt connectors and solder stuff back together. This is a common problem as these trucks get older.
Connectors:
Check this thread for a couple sources
You can toggle the thread at the bottom, then refer back to it via your 'my home' link; saves on a search. 
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http://www.walkablecommunities.org/
Seen on old Dodge-'I'll keep my money, my freedom, and my guns; you can keep the change!'
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Esquire812
Trail Leader
Reged: 04/25/02
Posts: 5688
Loc: Port Orchard, Washington
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I pull the harness out of the rig, lay it out on a sheet of plywood and tack it down with horse-shoe nails to keep the circuits seperate. Then just inspect each circuit from sensor plug side to ECU plugs and make repairs where needed. 85' Celica could have taught the trucks/4Runners better....its harness comes into the EFI from the backside of the plenum and doesn't have all the BS 90's and 180's that the trucks and 4runners suffer from.
Repair- peel harness coverings off, clean wires thoroughly and replace butt connector with solder joint and all splits are soldered as well. Cover all solder joints with heat shrink tubing then re-wrap harness to seal it from the elements.
~Darin
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88' 4x4 *22R-EB Gen II*
87' $Runner *22R-EB Gen I*
85' Sillyca 22R-Esq
"I LIVE IN MY OWN WORLD...THEY KNOW ME WELL THERE"
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Anonymous
Unregistered
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Darin,
You're a hero.
I Tore into the wiring and just like you suggested it was the crummy crimp connectors that were the culprits.
I owe you a nickel. It was such good information it might be worth a dollar?
I was surprised at the quality of the harnes, more like GM quality, junk. The fi circuit was literally falling apart. One wire was corroded out of the crimp connector. I cut all the crimp connectors in the loom apart ( most were ugly) and spent the day soldering. That was a fun deal.
The car was still at the repair shop, it was Sat and no one was working the garage. The owner let me work in the HEATED shop and it was heaven. I usually have so much crap in my shop that I end up working in the rain.
One thing that perplexes me is how in the world the injectors can fire individually when the trigger grounds are all wired together??? And since they are all wired together why are there two wires from the crimp to the ecu when one would do? The other confusing thing is when testing the terminals at the injector it showed two hots before I fixed the problem. This defies normal wiring logic, my wiring logic anyway. How can there be two hots at the injector terminals when the problem is one ground disconnected that is connected to three other grounds?? I asked the tech the same questions and he said I just fix the s--t, who knows, don't even try to figure out how it works. He said all 8 grounds on gm's are wired together. He seemed to think that all injectors fire at the same time and other sensors help regulate fuel flow. That also defies logic, but how can they fire individually when all the bloody wires are hooked together. It might take an electrical engineer to explain this???
Anyway, thanks a lot for the help,it saved the day,
John
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4WD22R
Body Damage is Cool
Reged: 10/25/05
Posts: 1287
Loc: Glendale, Arizona
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Don't try and figure anything relating to eletricity out, it is the devils magic and defies any rules that we earth bound people are bound to. Many people have sold their souls to be able to harness the power of eletricity and even they do not understand it. If it works it works if it dosen't then you must sacrafice a goat. That simple. It's what I do......but nothing eletrical works for me.....hmmmmmm, I still think it's the gremlins that live in my body panels, they eat wires you know. 
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-1986 TOYOTA
22R
ZUK coil rear
Torqued T-Bars
Marlin HD clutch
Newly rebuilt!! Runnin' like a champ!
AZTTORA #492
TLCA member
"I hear there's rumors on the Internets that we're going to have a draft."
--George W. Bush
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Anonymous
Unregistered
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Quote:
how in the world the injectors can fire individually when the trigger grounds are all wired together??? And since they are all wired together why are there two wires from the crimp to the ecu when one would do?
All 4 injectors fire @ the same time, twice per engine cycle.
on the cylinders where the intake valve is closed, the fuel just lays in waiting for the valve to open on it's turn.
If you think about it, with the engine running, things happen real fast and the fuel is quickly dispersed into each cylinder.
Chucky MoMo
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