[Mitch_c]

Picked up a 1986 5.0 complete with engine bay harness, computer, fuel pump. Got it installed but previous owner cut some of the wires.

Purchased a Ford Svc manual, but somewhat primitive.

No spark and fuel pump runs continuously when key on.

Purchased and installed new ICI, PIP, and Coil. No change.

Manual doesn't outline priming circuit or ignition circuit ( pin X does...)

Can anyone assist? Please do so. duh.gif

Been working on this for many weeks.

Mitch

 

[dkrasniak]

Any fuel pump should stop running if the designated pressure is reached. Do you have fuel actually pumping? Have you done a physical check of the pump? I had a pump that made no pressure, so it ran and ran. I'd recommend checking for fuel pressure at the rail and if it is making pressure there but low, you may have a damaged regulator bypassing it back to the tank or the pump is leaking either from a crack in the fuel line (inside the tank?) or the pump itself is damaged.

 

[Moses7797]

The fuel pump is powered by pin 22 which is a switched ground from ECM to fuel pump relay. The above could be a problem as well.

 

[squekster]

Picked up a 1986 5.0 complete with engine bay harness, computer, fuel pump. Got it installed but previous owner cut some of the wires.

Purchased a Ford Svc manual, but somewhat primitive.

No spark and fuel pump runs continuously when key on.

Purchased and installed new ICI, PIP, and Coil. No change.

Manual doesn't outline priming circuit or ignition circuit ( pin X does...)

Can anyone assist? Please do so. duh.gif

Been working on this for many weeks.

Mitch

For the no spark condition you need to check for
voltage at the coil's primaries. That's the two pin
connection. No voltage no spark.

 

[Mitch_c]

I have and external pump... Have not checked pressure, but more concerned that I have no spark...

I have checked the wiring harness for required grounds.. Pins 20, 40, 49, and 60 are grounded and manual I have shows this as correct.

I also show ground on Pins 4, 16, and 43??? Key is off, just using a test probe connected to the battery and probing the ECU cable connection (ECU removed)..

I'm at a loss.... Any suggestions?

:frown:

 

[uedlose]

are you testing the grounds with a test light or a ohm meter? one strand of wire could show ground but have a very high resistance. they need to be checked with a ohm meter for resistance. check the 10 pin connectors in the back at the intake make sure they are clean grab the harness and shake it and pull at it. That is a Ford wire test they call it harness shake no B/S on this LOL seen the 10pins connectors give problems time and time again. it is the pick up in the dizzy that tell the the ecm that the engine is turning and what injector to open and to start and stop the pump and fire the engine also. I would check it again to make sure the new one is not bad.