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Discussion Starter #22
back probe the PIP on the tfi

what is the voltage during crank?
Apologies for late response. Work schedule and moving son back to college has kept me away.
I need help on how to setup testing the voltage on pip. I researched and one site said to make a led tester and hook red to battery and black to the pip wire on tfi. Is there another way? How do I use the meter?
I did check a few things. Verified 12v at TFI, verified ground to tfi, and grounded the self test to fuel pump pin and it came on and ran continuously.
I also pulled the distributor cap and verified the rotor turned when engine cranked. Just to rule out a sheared roll pin. The distributor shaft has up and down play that my 91 doesn’t have. Only oddity I could visually see and check.
 

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Not to try to confuse things, but isn't the fuel pump relay under the driver seat? My 90 has it there and I know that other foxbodies I have owned had it there.

If its there, put a jumper between the 2 heavier gauge wires and fuel pump should come on. If true, replace that relay and see whats next
 

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Discussion Starter #24
Not to try to confuse things, but isn't the fuel pump relay under the driver seat? My 90 has it there and I know that other foxbodies I have owned had it there.

If its there, put a jumper between the 2 heavier gauge wires and fuel pump should come on. If true, replace that relay and see whats next
Thanks for the input. On the 92, it’s under the mass air meter. My 91 is under the seat.
Based on what I’m seeing, the relay and pump look ok. Jumping the self test connector to ground did engage the pump. From what I understand, that says the fuel pump circuit including the relay are ok. Correct?
Even with the fuel pump running though, I’m getting no start. Happened all at once. Also can’t get any codes from the computer. It won’t go into self test.
So..., it’s either a failed pip in the distributor (tells the eec the engine is cranking/running which kicks on the pump and opens the injectors) or the eec is bad.
At least that’s what I understand. More testing needed.
 

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you dont use a LED light, use a incad test light

anywho

put your volt meter in DC volts, anything 0-10 or 0-20 volts not in auto ranging

one lead backprobing the PIP at the TFI or ecm, which ever is easier

one lead at batt neg or a good body ground

what is the voltage in crank?
 

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Thanks for the input. On the 92, it’s under the mass air meter. My 91 is under the seat.
Based on what I’m seeing, the relay and pump look ok. Jumping the self test connector to ground did engage the pump. From what I understand, that says the fuel pump circuit including the relay are ok. Correct?
Even with the fuel pump running though, I’m getting no start. Happened all at once. Also can’t get any codes from the computer. It won’t go into self test.
So..., it’s either a failed pip in the distributor (tells the eec the engine is cranking/running which kicks on the pump and opens the injectors) or the eec is bad.
At least that’s what I understand. More testing needed.
The other day I had my 91 EEC and stock harness on the bench and when I applied power to the EEC power relay (simulating key on) the EEC primed the pump relay, and this was with the harness on the bench so no TFI was plugged in. If you aren’t getting a prime at key on and you have already tested the FP relay and it’s wiring from the EEC as good, I think your computer is the culprit.
 

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we will address that in good time

suffice it say a prime in key in "RUN" does NOT always come on in certain situations

remember we already know the ecm is NOT getting cam/crank signal, CEL light is on in crank
 

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Discussion Starter #28
I should get the results tonight hopefully for the PIP output.
I've had my 91 (other fox) since 95 and have never seen this with that car. So this level of troubleshooting is new. I now use a microsquirt in that one due to the 351 and the desire to learn how to tune it. The 91 never failed to start and that was through many modifications, drag racing, nitrous, etc. Stupid reliable. As a matter of fact, the old 302 always had the factory distributor and module that came new in 91- never failed and that included turning that motor 7500 rpm's racing it for a few years. SO when this one didn't start, it stumped me. Its like looking at a two year old car that has never seen rain. I honestly cant wait to figure it out and hopefully later when others search for a similar issue will find help on theirs.
Thanks again for the tutoring.
 

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why do that

when you can a spark tester at the end of a plug

anyhow, you can have spark, icm needs no input from the ecm to make spark

without rpm input, already seen with CEL on, it will still be a no start
 

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Fuel pump running constantly with KOEO and no start = 1 of the 3 ECM capacitors is bad and it's the middle of the 3. Thank me later.
 

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Discussion Starter #33
Fuel pump running constantly with KOEO and no start = 1 of the 3 ECM capacitors is bad and it's the middle of the 3. Thank me later.
Thanks. I’m actually getting zero pump koeo. It engages when the self test connector is jumped and stays running until key off.
 

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Discussion Starter #34
So my sole update for the evening. With my son at college, and wife busy this eve, I had no one to crank the motor while I checked pip output. So I did it koeo by loosening the distributor and rotating, listening for injector click or fuel pump prime. Nothing happened. Read about this method through a search. Any merit to it? And, I also verified I could hear the eec relay click while inside the car ko.
 

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400 rpm?

why didn't you measure voltage while spinning it by hand?

you could have wedged the throttle to WOT, then cranked it with a screw driver at the solenoid, 1 hand needed only while watching the meter

no need for another person, get creative, man.
 

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Discussion Starter #36
Ok. So voltage at PIP was 5.xx volts. Don’t remember exactly but was steady in the 5’s.
 

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IT SHOULD BE 0-10v if you do it slowly, but if was cranking and you got 5volts, that is good

if you did this at the tfi, will need to confirm at the ecm, as the wire could be an issue

also have you tried disconnecting the spout and cranked?
 

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Discussion Starter #38
I did remove the spout but no change. And I checked the voltage at the TFI.
 
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