Troubleshooting a 1988 Ranger 2.9 gasser

[Michael Fowler]

I need some help. I am trying to help a young neighbor who has the above vehicle, and it won't start. He even had it to a "professional" mechanic who was unable to help, and, in fact, made things worse by cutting the fuel pump relay harness for some unknown reason.

So far here is what I have done--
If I jumper the fuel pump wires, I can hear the fuel pump hum, and I get 40 PSI at the fuel rail.
NO SPARK--Using a timing light on the coil wire, I see no flashes. Even when primed with a splash of fuel down the intake, it doesn't even hiccup.
Using the procedures in the Chilton manual, both the Ecoil, and the TFI module ( distributor-mounted) seem to be OK.

MY QUESTIONS
1) Is there a signal FROM the fuel pump relay that triggers the computer for spark?
2) How to test the rest of the distributor.
3) Any other advice/ suggestions??

I have tried to ask on Ford-Truck forum but after signing in, anything I try is met with a response that I do not have permission to access that page--I can't even contact to moderators to tell them. It is frustrating!!

So are spark-ignition engines--At least with a diesel, you just KNOW its a fuel problem.

 

[tknomaj]

use DVOM and set it on a/c voltage connect it to the two wires coming out of Dist it is a oval connector(kind of) have someone crank over engine while you watch meter does it move to about 3v then down to nothing ? if so dist is good and replace ignition module. also check for injector pulse with small light bulb solder two wires to contact points on bulb and un plug one injector and push wires into connector and have someone crank engine over and watch for light to flash no flash and module is bad

 

[Michael Fowler]

THANKS!!
Two additional questions.
Are you referring to the ignition module in both of your trouble shooting sketches?
To be clear, the Ignition Module is the TFI, or are you talking about the computer in the passenger kick panel?

Thanks again.

 

[adrianspeeder]

First head on over to the top little truck site www.therangerstation.com and poke around if you want to talk to those guys.

But if I remember right without my book, key on clicks the EEC relay, which then the computer drives the fuel pump relay.

Adrianspeeder

 

[Black dawg]

check the ground wire at the battery. it is a ground for the ecm. in 15 years of working on cars, ive had 10 rangers towed in that only had a bad connection at this wire.