94 xlt will not start!!

[jamesjones]

hey guys, hopefully someone can help me with this problem so here it goes. I was driving and everything was fine when i went to the gas station, parked, filled it up and it would not start back up. It's got good fuel pressure, i tested the ignition systed and thats good, the fuel injectors are getting a signal from the pcm, and it will run if i pour gas down the throttle body, but only until the gas runs out. it has a new battery new cables new filter and like i said it's got good fuel pressure and will run as long as I pour gas down it. Any ideas?

 

[Chew_12]

Whats it do when you try to start it?

 

[Robb]

What kind of fuel pressure exactly does it have?

How did you test the ignition system?

How did you test the "signal" to the injectors?

How do you pour gasoline down a horizontal throttle body? How are you pouring it in? Is the intake tube disconnected during this? How does it run with no MAF in the circuit?

 

[jamesjones]

when i try to start it, it just turns over, sometimes it will start then immediatly shut off. The fuel pressure is at 40 psi i used a fuel gauge to test that, and i tested the voltage and resistance in my ignition system with a mulitester. I tested the signal to the injectors by probing the leads while the car was being turned over and it was getting an intermediate pulse. I've got an old fuel rail because i've replaced the motor a couple of years ago so i disconnected my return fuel line and connected the old fuel rail and stuffed it down the throat of the throttle body then turned on the ignition so the fuel pump will send gas to the cylinder. then reconnect everything and turn it over and it starts right up.

 

[anthonytony]

out of time maybe....or cats stoped up is it backfiring or spitting when u pour gas too it .old school telle me if your pouring gas too it to get it too run its a fuel pump problem.

 

[jamesjones]

no, it doesn't backfire or anything. it runs great until it burns up all the gas. if i pour more in, it starts right back up. it doesn't have a distrib. so how would i check the timing? and how would i know if the cats stoped up?

 

[superchef]

Just a shot in the dark - have you checked the fuel cutoff switch?
It's Located under the passenger side kick panel

 

[Con Seann3ry]

*subscribing*

 

[jamesjones]

yep, checked the cut off switch and today tested the tps sensor and crank sensor they were both in working order. im going to check the cam sensor and after that i'm stuck. any more ideas?

 

[TPLYNCH]

Do you hear the fuel pump whining when you turn to on, before going all the way to start? Try switching the relay for the FP and see what happens. Also, does it have the Ford PATS alarm system (key w/microchip) or an aftermarket alarm system?

 

[jamesjones]

no alarm system or anything and i can hear the fuel pump when i turn to on. i pulled the fuel pump relay and turned to on and didn't hear anything but when i plugged it back in fuel pump kicked back on but it still won't start.

 

[TPLYNCH]

Maybe there is something plugging the fuel rail between the pressure valve and the injectors that is not letting fuel in??? If FP is running, and you have pressure on the rail, and run if you manually give it gas, then it's got to be something in between.

 

[MrShorty]

I think Tom's on the right track. You checked the electrical signal to the injectors, and it appears they are being told to fire, but are they actually opening? If you stick a stethoscope on them, can you hear them open and close?

A couple other questions:
Does the fuel rail hold pressure when the pump shuts off? Does the fuel pressure stay ~40 psi while trying to start? If you unplug the fuel pump and try to start it, how quickly does the fuel pressure drop off (see if injectors are opening)?