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Ron, ASE Certified Technician
Category: Ford
Satisfied Customers: 33019
Experience:  23 years with Ford specializing in drivability and electrical and AC. Ford certs and ASE Certs
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1986 ford ranger: liter..fuel pressure on the fuel rail.

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1986 ford ranger 2.9 liter. I have spark. I have fuel pressure on the fuel rail. I dont have any injector pulse(tested with noide). I have proper voltage at each injector. Chaged TP sensor. Replaced computer. What other test should I run? Didi I miss something?



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Located the pressure feedback EGR (PFE) sensor on driver's side of the upper intake plenum, just behind throttle body. It is a small, black, box-shaped sensor with a three-wire connector and one exhaust pressure hose. Unplug the PFE sensor. If the vehicle now starts and runs, replace it.

Customer: replied 8 years ago.
Just unplugged the PFE sensor. Still no start, Ron?


Thank you for asking your question on Just Answer.


Ok so you have spark and good fuel pressure but no injector pulse. Was this a new PCM?

Check the Powertrain Control Module (PCM) power and ground circuits, from pins 40 and 60, to the battery negative pigtail connection, for a poor ground.

Customer: replied 8 years ago.
No from the wrecking yard. All the numbers matched.
Ok but read my last post and check your grounds. If they check ok then you likely have a bad PCM. I suspect you have a bad ground as this can allow it to have spark and fuel pum operation but no injector pulse.
Customer: replied 8 years ago.
If I spray starting fluid in it, It fires right up
Yes it would, because you are supplying it with fuel. The same signel for the Ignition modual allows the PCM to ground switch the injectors from the PCM. Check pin 40 and pin 60 for a good ground from the battery. If you have a good ground at both pins then the PCM is bad. The 1986 had a problem with bad grounds at the battery. There are to wires that come from the negative battery pig tails.
Customer: replied 8 years ago.
WHich pins are 40 & 60?Do u have a diagram? And what shold my reading be on my DVOM? Off the battery there is one ground going to the main harness, and the other is just hangin there?
On the connector at the PCM in very small letters you will see they are numbered. You will have to remove the black plastic cover on the harness where it goes into the connector to see them. With the connector unplug from the PCM they should be very little resistance. In the range of .003. Start first by checking the 2 pig tails that come of the negative battery cable at the battery.
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