Hard start issues.

[Cws91eddiebauer]

I have a 91 explorer that was running good and then nothing. Changed starter, relay, battery icm, and nothing. We figured out there was no spark so we changed the crankshaft positioning sensor and it got spark. Took a long time to get it started but once it started it ran great. Turned it off and same issue. Fuel pump and filter are good so we changed the pressure regulator. Same issue. Plugs are new.coil pack? it almost acts like the timing is off but again once it starts it runs great.

 

[Cws91eddiebauer]

Well, I think the fuel pump is good. It's only 2 years old. it spits and back fires when cranking before it starts.

 

[MrShorty]

First thing I'd probably do is be certain the pump is good -- put a fuel pressure gauge on it and see if the pump is generating sufficient pressure.

edit: I didn't realize until I saw in your other thread that you have already checked the fuel pressure.