Ex Dies while running, now won't start

[PekingMan]

93 XLT ,won't start

Hmmm,

Going down the road, hit a light bump, all of a sudden, no throttle response. Smooth as can be and a few flickers of the battery light. I pull over and shut it off, but it won't start back up, acting as if its a dead battery. So I replace the battery, now the engine turns over but won't start.

Can't really determine whether its fuel or spark. I pulled a plug (which are good), it sparks, but not well. Checked all plug wires, ignition coil, fuses and nothing seems wrong except the resistance between the coils are a little high. I don't think its fuel since it died smoothly (no sputtering) with no indication that the engine was being starved of fuel. However I checked the fuel system, and nothing seems to be wrong with it short of looking at the fuel pump, which I prefer not to mess with since it requires dropping the tank. I do not however, get the 1 or 2 seconds of a "whirring sound" after the ignition is put into the on position.

I'm kinda out of ideas. Any else have a suggestion before I continue to waste more of time. :frustrate

 

[Alec]

Have you checked the wiring going to the coil? Sounds like something knocked loose.

 

[PekingMan]

Yeah, I checked it and the harness is providing the correct voltages when the ignition is in the on position.

 

[A Wise Guy]

A stab in the dark here. Do the 1st gens have the schraeder valve on the fuel rail that supplies the injectors (if it has any)? I got an air bubble once and until I let the bubble out of the rail all the truck would do was crank.

 

[PekingMan]

I've had no time to work on it until now. With that in mind.....

I'm getting spark, so that's not the problem. I know it has something to do with the fuel pump.

There is no pressure in the fuel rail as I found out with the shraeder valve. The relay is fine so I have narrowed it down to two possibilities....

1) The fuel pump is bad and needs to be replaced.

2) The electrics to the fuel pump relay. When I do an electrical test on the fuel pump relay connections, I get some stange results. One terminal is always hot when the ignition is off, terminal 30, duh. When in the ON position, terminal 85 or 86 (I can't remember) goes high while the other stays low, therefore powering up the control circuit for the relay. The strange part is the terminal 87, not 87a also goes high to about 9.5V. I don't think this is right and I have no idea what would be causing it.

I think 87 going high is causing the fuel pump not to activate but I;m not sure. Any ideas???!!!

 

[AlaskanJack]

could the inertia switch have tripped??

 

[PekingMan]

checked that, didn't seem to be the problem