FJ62 Help Needed (1 Viewer)

[Woodman]

So I had a perfectly running cruiser (1989 FJ62) before changing shackles and replacing the battery. Vehicle sat on jack stands nose down for 48 hours awaiting parts. Did rear shackles and replaced battery and 1st crank it ran like crap. Since it will crank, fire then die within 2 or 3 seconds.

SO,

I have jumped terminals and can hear fuel pump working. Vehicle does not run when started with jumpers in place, it simply cranks/fires/dies like it does without jumpers in place.
When I remove key from ignition and I can hear relay in passenger kick panel cycle

So one of my assumptions is that sitting nose down the fuel sock could have gotten loaded up with whatever debris is in a 25 year old tank.

Last tidbit. If I let it sit for 15-20 minutes between start attempts it will start/run/die at the longer 3 second interval. Subsequent starting efforts after the initial 3 second run time are much shorter in duration, crank/start/die with 1 or 2 seconds before it dies.

Any other ideas or tricks to try? It was running perfectly before this seemingly benign shackle and battery swap.

Thanks in advance!!!

 

[Jerry D.]

Look at your Air Flow Meter plug/wiring. It will shut off the fuel pump after crank/start if not connected right.

Jerry D.

 

[Woodman]

wires look good, appears to be snug and well attached. Is there a testing technical testing procedure or more of an inspection item? Thanks Jerry for your input. Any other ideas?????

 

[60Works]

Fuel filter?

Any codes?

We're any wires obviously disturbed when changing the battery?

 

[Woodman]

No codes, wires seem ok, one wire in fusible link is a little tattered but it was that way prior. Filter is newish

 

[Jerry D.]

Look at the pictures in the last post in this thread: https://forum.ih8mud.com/threads/fj62-intermittent-starting-issue.836292/

If the fuel pump runs during cranking to start the engine, then the Circuit Opening Relay should be OK. It may be possible that one of the coils is burnt out. You could check OHMs across STA and E1 to verify there is some conductance across it.
Take off you air filter and open the flap in the Air Flow Meter slightly with a screwdriver or pencil. Start the engine, if it stays running then you need to look into the Air Flow Meter.

Jerry D.

 

[KLF]

Jumpering across the +B and Fp contacts in the Diagnostic connector takes the Air Flow Meter out of the system, bypasses it. Sounds like he's done that.

Test the coil, and look carefully at the wires on the ring terminals where it is connected. My '88 did this exact thing to me once, would start but not stay running. Found one of the wires to the coil just about to break, it had only one tiny strand of the wire left. Cut the wire off, crimped a new terminal, it was fine after that.

 

[Woodman]

Continuing to head scratch on this. pulled a plug tested spark.........it was orange and not what I would consider strong...........at the plug. So perhaps weak spark is now in the equation? Pulled fusible link checked it end to end cleaned connectors. Now I'm getting no start............just starter turning over but haven't had the brief start up then die in many many attempts.

Any other thoughts Mud gurus?

 

[TrickyT]

Just to confirm, when you jumper together terminals +B and FP in the diagnostic test connector on the PS firewall and put the ignition switch in the ON position, the fuel pump runs and you hear fuel running through the fuel rail and FPR, correct? You can also loosen the banjo fitting on the cold start valve and confirm fuel comes out when when the jumper is in place and ignition on. If this is true, then the EFI Main Relay and Fuel Pump are good.

Next try starting the engine with the +B/FP jumper in place. If it runs then either the Circuit Opening Relay, Air Flow Meter, or associated wiring are suspect. If it doesn't run then you likely have a spark issue. That could be a bad coil, igniter, pickup coils in the distributor, or associated wiring connecting these devices.

The first line of you post said all was fine before you changed the battery. (I'm discounting the shackles because they have nothing to do with the engine.) So I would carefully check all wiring around the battery for anything that might have gotten disturbed when you changed it out. For example, the fusible links are right there and one may have gotten broken or damaged. Bad fusible links can definitely cause the type of problem you describe.

Post up what you find during your testing.

 

[Woodman]

Update: So I inspected the fusible link for severed wires, etc. Knocked off present corrosion and retaped and reinstalled, cleaned connectors with electronic connector cleaner. Previously when I jumped Fp and B+ I could hear the pump pumping, tried to start and it did but it died. I was trying to rule out the obvious so I disconnected the outlet side of the fuel filter and again rejumped Fp and B+ thinking that if I have gas coming out then the fuel pump/sock, line and fuel filter would all be good. With this jumper attempt I DO NOT HEAR THE PUMP PUMPING????? So no gas coming through the outlet of the fuel filter. So I feel like I'm chasing my tail...............first jumper attempt I clearly heard the pump pumping...............now I hear nothing. Seems odd that the pump would just give up the ghost like that..........but??????

Is orange spark sufficient? I was expecting a sharp blue spark?

 

[TrickyT]

Chase one problem at a time. It's definitely not going to start without the fuel pump running, so figure out what's wrong with that as your first step.

It's more likely to be an intermittent electrical connection than the pump suddenly going bad. And intermittent connections are often hard to track down, so hang in there.

With the ignition key in the on position, measure the voltage at terminal +B of the underhood diagnostic connector. It should be 12v. If you don't get 12v, then it's a bad fusible link or fuse or EFI main relay or associated wiring or -- and this is very remote -- a bad ECU.

If you do get 12v at the +B terminal but the fuel pump still doesn't run with the jumper, then it's either a bad pump or the wiring going back to the pump or a bad connector along the way. To determine which you'll need to get to the top of the gas tank so that you can put a meter probe on the pump connections. One of the pump connections goes back to the FP terminal and the other goes to vehicle ground.

The link in post #6 above leads to a simplified wiring diagram for the fuel system.

 

[Woodman]

Doing nothing and simply turning the key to start my day with the cruiser it cranked up and ran smoothly for 10 seconds, then died. Would re-fire for another few seconds. Jumping the terminals I hear the fuel pump today!?1? Volts at B+ are 11.95

Back to the coil.........is orange spark acceptable or would that be considered weak?

Cranks, runs 10 sec, dies............will restart....................any new scenarios to consider?

 

[TrickyT]

This just sounds more and more like a fusible link issue to me. You should read this post by BTUMAN: https://forum.ih8mud.com/threads/fusible-link-question.258630/page-2#post-9595513.

 

[Jerry D.]

The Fusible Link has to be good or the fuel pump will not run by jumping the +B and FP in the check connector, nor will the fuel pump run in the start mode.

The only common items that will allow the fuel pump to run in start and not in the run position is the Circuit Opening Relay or the switch in the Air Flow Meter.


Jerry D.

 

[TrickyT]

The Fusible Link has to be good or the fuel pump will not run by jumping the +B and FP in the check connector, nor will the fuel pump run in the start mode.

The only common items that will allow the fuel pump to run in start and not in the run position is the Circuit Opening Relay or the switch in the Air Flow Meter.

Jerry D.

I disagree. The fusible links need to be capable of passing enough current to power the vehicle and do so without causing significant voltage drop. Maybe Woodman's links can do that and maybe they can't. The intermittent nature of his problem makes the links suspect in my book.

In post #10 he said he jumpered +B and FP and the fuel pump did not run. This test bypasses the COR and AFM. So either he didn't put the jumper in the right terminals of the diagnostic test connector or something else is in play.

The fusible links are know to cause problems like this. And they are easy to replace. If he replaces them and it doesn't fix his problem, then he's out a few bucks and has a spare set of links to toss in his glove box for another day.

 

[Woodman]

So I have rebuilt the fusible link, reinstalled and no change in performance. Crank/start /die. The more you try and restart the less luck you have. First start of day it will run for a few seconds, next effort little less, then just starter turning over.

Us there a test for COR or the AFM?

Thanks for talks continued efforts!

 

[TrickyT]

Once you get to the point where the motor just turns over but won't fire, you need to determine if you are getting fuel to the fuel rail. For example by loosening the banjo bolt on the cold start valve and/or with a fuel pressure gauge as discussed previously. If there's fuel then it must be a spark or injector problem. If there's no fuel then it must be something in fuel pump circuit.

 

[Woodman]

No fuel at the CSV. So for today's tail chasing...................jumpered Fp B+ no fuel pump.........went to the back to test wires..........dropped flashlight getting into rear of truck..........and..........fuel pump started pumping! So it now appears to be a wiring issue somewhere between the pump and the diagnosis port. Perhaps the connection in the jack/tool access area or top of pump?

 

[Jerry D.]

Good luck...


Jerry D

 

[Woodman]

Alright Boys............stick with me here.........I feel confused but like perhaps on verge of progress.

So with Jumper I can confirm pump is working consistently now and fuel is coming out freely of the cold start banjo bolt when loosened.

I've removed the rear quarter trim, rear jack assembly and checked/manipulated the wiring back there to see if I could cause any interruption in the fuel pump pumping while jumped. I can't, so wiring appears good and looks good.

The truck will crank/start/run then die after a few seconds. Battery does increase in voltage when running so Alternator appears to be good.

But here is the new riddle. When I leave the truck/battery connected to the jump box/charger it runs forever.........when jump box, reload its charge impulse the truck stumbles but can be kept alive with the throttle until the jump impulse is restored and then it runs per normal.

SO, there is some sort of drain occurring or short or something that prevents the rig from running on its own but allows it to run when on auxiliary power?

Any ideas????

As a refresher...........I have no codes...........my CEL illuminates per normal when key inserted.

Thanks in advance!!!!