identity

Hi everybody -
I've got a problem and I hope you can offer some suggestions or confirm I'm looking in the right direction.
Tall deer: '94 3VZE, engine died suddenly and will crank but not restart. Pops EFI fuse immediately when cranking or if FP jumped to B+. Please help.

Long story: Last Saturday morning I replaced the fuel tank(original tank and pump got gnarly after sitting for a year waiting for me to rebuild the engine, so I replaced them... but I pinched the new tank during installation and had to patch a hole... the patch held for a year or so and started hissing again, so I got a new tank again). I reused the pump and sock because they were not very old. Nothing appeared corroded or otherwise damaged. Truck started and ran fine.
That evening my wife took the truck out, and the cooling fan came apart on the freeway after a few miles of driving. The flying blade chunks holed the airbox and punctured the radiator, which sprayed coolant onto the front center of the engine. She pulled over immediately and called me freaking out because the car broke and was on fire(she saw the steam...). Truck did not overheat. I replaced the radiator and fan in the parking lot that night and drove home, all was well.
I drove the truck to work and back with no issue on Tuesday, then to work yesterday. Drove fine, no issues(CEL has been on for some time, EGR code).

On my way home yesterday, after driving about eight miles, the engine died abruptly - no loss of power, no hint of a problem, tach went to zero and that was that - and would not restart. Dash, lights, blower etc had power, engine cranked but wouldn't fire. I got it into the parking lot using the starter and with the assistance of a couple of helpful dudes. My wife came and picked me up.
We came back later with some tools and a Haynes manual, and I started poking around. The exhaust didn't stink like gasoline after cranking for some seconds, so I started looking for a fuel issue. The 15A EFI fuse had blown, so replaced it with a spare and cranked the engine while she watched. She said she saw a visible arc and the fuse blew, but couldn't be more specific so I replaced it again and moved more slowly. I did a pretty thorough visual inspection and found no broken wires or burn marks, and no apparent damage from the fan shrapnel or water spray(it had been spraying down and toward the passenger side, near the power steering pump).
I put the key into run, CEL came on and fuse remained intact.
I turned the ignition off, pulled the EFI main relay and tested according to what I found by searching, got open across the contacts which are normally open and 80 ohms across the coil. Same results with the circuit opening relay, coil measured 80 ohms and switch contacts were open. I checked the O2 sensor wire everybody says to check, it's fine and well removed from the exhaust.
I then jumped FP and B+, turned the key to run, and the fuse immediately popped.
I pulled the access panel under the seat and checked resistance across the FP connector, got 0.0 ohms(I have read that it should measure somewhere around 5-7 ohms?). I'll check with a different meter and see what it comes up with.
My mother-in-law then called to say that the kids had let a rag go down the the bathtub drain and the water wasn't draining, so we called a tow truck(thanks, insurance policy!) and I went home and dealt with that mess while my wife waited for the tow. Truck's at home in the driveway now and I can drive our van, so I'm not as stressed out, but it's gonna need to be fixed so I can SELL IT AND BE DONE :p

I will readily admit that electrical diagnosis is NOT my thing, so any pointers or suggestions will be greatly appreciated. At this point I am expecting to have to pull the(full) fuel tank and replace the pump, or at least deal with some wiring. Is there something I'm missing?

Thanks a lot for reading and for any thoughts you might have.
- Ben

identity

RAD4Runner

Re: COR, Relays, etc... Doubt the components last. Toyota parts are almost -always bullet-proof. Oftentimes problems come from bad wiring.
You have a short to ground. Inspect your wiring from FP connector, to fuel pump, including fuel pump.

[quote]I will readily admit that electrical diagnosis is NOT my thing, so any pointers or suggestions will be greatly appreciated...

Best to take fuel pump out of the fuel tank to test it, to be safe.

A picture paints a thousand words. Pls put us near / in your truck.
Sorry, what do you mean by across? Where did you put the test probes? Ignition off? In Accessories position? In Ign ON position?

identity

Thanks for the reply RAD4Runner.

Fair enough. I have read of enough people having relay issues that I figured it'd be a simple thing to test, but it seems like that's the wrong direction entirely.

I unplugged the fuel pump pigtail from the truck connector and placed the probes on each pin of the FP pigtail.
I am going to head outside now and see if I can get anywhere looking for a short to ground. Will follow up later.

Thanks again -

identity

Well, lucky me.
I went out and started poking around, unplugged the FP and plugged in a known good spare, jumped FP and B+, and the thing spun just fine when I turned the key. Problem is on the FP side of the connector. I have pivoted the tank down a bit but haven't found anything obvious... guess I will get back out and finish pulling the tank.

Good thing my wife was nice to me and filled it up

Will advise later. Thanks -

identity

Found it. The insulation on a solder joint had slid and uncovered the conductor and allowed it to ground out on the pump bracket. I'm not sure how to cover the joint so it doesn't happen again. I used shrink-wrap tubing last time, will have to see what others have done.

identity

Fixed. At least, it ran in the driveway for half an hour.
I should have been more specific earlier: the heat-shrink tubing got soft and swollen and slipped out of place to expose the solder joint, which joint then moved around for who-knows-how-long until it touched the fuel pump bracket and caused my short.
What I ultimately decided to do is clip the wires, tin the ends, then slip some fuel hose over one end, crimp the wires with PVC butt connectors, and slide the hose over the butt connectors. The hose fit quite snugly around the butt connectors, so I don't expect it to move. It'll be another layer of protection against shorts, abrasion etc.
I hope.

Thanks again RAD4Runner, and anybody else who read with intent to help. I don't have any beer in the house, so go ahead and have one for me...

Take care,
Ben

mholme

RAD4Runner

Good Job, Ben!
Doubt the components last... Yada-yada - LOL!


.Have a beer, AYE!

identity

Ooooooo, excellent choice!
If you like Old Rasputin, see if you can find Black Boss Porter or Rinkuskiai Werewolf(I might be partial, Lithuanian background and all).

Thanks again, all's been well over the weekend and on the way to work this morning.
Take care!
- Ben