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John,

           It is below freezing here and the truck is out doors. Will not do any more until tomorrow at the soonest.
It would seem to me there should be a way of testing the items verses changing parts / easter egging. Also, what kind of readings should I get at the injectors with key is on , also when cranking the engine when working correctly.
            I don't mean to sound un-appreciative, however ,I trouble shot it and told you what was wrong items it could be and you told me to change them and if it wasn't them it could be the EEC .
             All of this I knew , I will try unhooking the MAP sensor as you suggested and then see about replacement parts if I don't receive any info on how to test or rule out an items .

                                         &nbs p;              Thank You , Ray

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1987 Ford Ranger 2.9 L

Already Tried:
John, It is below freezing here and the truck is out doors. Will not do any more until tomorrow at the soonest. It would seem to me there should be a way of testing the items verses changing parts / easter egging. Also, what kind of readings should I get at the injectors with key is on , also when cranking the engine when working correctly. I don't mean to sound un-appreciative, however ,I trouble shot it and told you what was wrong items it could be and you told me to change them and if it wasn't them it could be the EEC . All of this I knew , I will try unhooking the MAP sensor as you suggested and then see about replacement parts if I don't receive any info on how to test or rule out an items . Thank You , Ray

Customer (name blocked for privacy)

Status: Closed Value: $1

Greetings;

I don't mean to interfere here, but I noticed in your original posting that you state there does not appear to be any power getting to the injectors.

The fuel injectors should have 12 volts at one of the wires in each injector plug whenever the key is in the run or start position. The ECM grounds the other wire (actually, it pulses the ground off and on at varying intervals to vary the amount of fuel injected) when the engine is being cranked or is running.

You should use a DVOM, logic probe , or noid light to check for pulse on the ground side; using a 12v test light is not recommended because the high current draw created by a test light can result in damage to the switching transistors in the ECM if excessive current is allowed to flow through the ECM. Using a 12v test light is OK for checking the power side of the injector plugs.

If you confirm that there is no b+ present at the injector plugs, I can help you troubleshoot the injector b+ supply circuit; that is the logical place to start diagnosis here, I would think. The B+ to the injectors does not involve anything computer related, and if it is not present the engine will never run. I think I would concentrate on this first, leaving the fault codes for later as they appear to not be related to the primary no-start issue you are experiencing, and could even be in memory from a previous fault years ago if ECM memory has never been cleared following a previous repair.

Thank you steve, Confirm , there is no B+ present at the injector plugs.

Ray

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