92 X 4,0 won't run

[deerejohn606]

My x has been hard to start for quite a while but now it doesn't want to run at all.The last time it ran all was well after a hard start. Fires but doesn' t won't run. Shot of starting fluid fires it up then sounds like it runs out of fuel.tripped the schrader valve on fuel rail to find just a dribble of fuel. Sounds like the fuel pumpruns for about 5 seconds and stops, just like it always has. how do I check the pump independent of the system while still in the tank. I can't tell if the pump is weak, the fuel pressure regulator is stuck and is bypassing by the rail and returning it to the tank. I'm trying to avoid replacing everything one piece at a time, only to find I've spent $300 and careful proceedures could have diagnosed a quicker and cheaper cure.
Also feel free to E-mail me at deerejohn606@aol.com As usual thanks for your help!!

 

[sncwfo99]

I would say if the regulator is stuck and causing the fuel to bypass I would change it first. not positive but that sounds like your problem. also try doing a search on the subject, should turn up alot of useful info for ya.

 

[Pheonixx77]

if your regulator is bad sometimes you can pull the vac line and see fuel. also a good check is to find a buddy with a fuel pressure tester, or buy one $$ and hook it up to acc port on fuel rail, and check pressure i would guess pressure should be around 45 ish...if the pressure is wrong someone chime in here.

 

[MrShorty]

The best check for fuel pressure is a fuel pressure gauge. With the vacuum line disconnected from the FPR, the pressure should be 35-45 psi, the system should hold pressure when the pump shuts off, and the pressure shouldn't significantly decrease when accelerating the engine.

 

[deerejohn606]

92 x won't run

Pulled the fuel pressure regulator, and did what I shouldn't,fitted a fuel hose in the spot that the f/p/r came from and turned the key on. f/pump runs but no fuel. Pulled the tank and pump, and bench tested the pump.Pump will pump fuel but no where near 35 psi . Ordered a sending unit and pump assembly. What a bear to remove the fuel line fittings on the tank. The internal spring locks buggered up on both lines. I'll keep you posted as I go. Many thanks for the replies!!

 

[deerejohn606]

92 x won't run

The old pump only had 7 psi when I tested it. The new pump supplied close to 40 psi, And the F/P/R bypassed at 39 psi. I hope these figures and oddball test proceedures help someone else, as it was hit and miss for me.
By the way, the old X lives again!!!

 

[andypinto]

deerejohn606:

Before spend a lot of money in a new fuel pump, please check the fuel filter.
During months I have a pinging ans engine hesitating problem in my 92 XLT 4x4.
I do everything to fix it: MAF cleaning, Sea Foam, intake manifold bolts retight and so on. Result? nothing.
Finally, I remember that the fuel system has a filter and that I never serviced it.
Well, when check the fuel filter it was totally clogged. I really don't understad how my X runs during all this years with this thing on it.
I change the fuel filter ( a couple of bucks and 15 minutes, that's all) and now the pinging and the hesitation just dissapear.
The engine runs fantastic and I'm very happy.
So keep it simple and troubleshooting the problem from the easy to the hard.

Good Luck!!

Andy.

 

[lonestar]

definately change the filter. After spending $150 on a fuel pump assembly, you don't won't to find out that a clogged filter is what caused the first pump to burn up.