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Discussion Starter #1
Hi all:

Can the FPR cause a vehicle to NOT start? I'm getting the motor turning over but no start.

Wires, Rotor and Cap look good, I hear the fuel pump engage when I turn the key. I was directed to the FPR on another post and found that if I pull the vacuum line from it, I smell fuel. Could this cause the no start or is the a result from lengthy attempts to start the vehicle... it turning and turning but not starting?

Do I buy the FPR without doing further troubleshooting or is that risking me falling into the "buying parts I don't need" ballgame?

PLEASE HELP!!! Thanks!
 

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put a fuel pressure guage on the rail and turn the key to on. you should see 30-40 psi or there abouts with the engine off. 0 pressure and you can hear your pump, you may want to cycle the key a few times to see if the pressure goes up.

also check your plugs to see if they are wet or dry.
 

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Discussion Starter #3
Sound good, jopes... I was planning to grab a pressure tester for it in the morning. I'll also pull the spark plugs as you suggested. Should I go ahead and pull each one and check them out while I'm at it or for these purposes just pull one?

Thanks!
 

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yo,
Also, Do a Self Test for Diagnostic Trouble Codes (DTC)s by my pal, BroncoJoe19
Since you can't get it running to heat eng to norm op temperature for Key On Engine Running (KOER) portion, just do the Key On Engine Off (KOEO)
The engine temp must be more than 50°F to perform the KOEO
turn off all accessories/lights, etc.


Make sure A/C is off and transmission is in Park (automatic) or in Neutral for a Manual & release clutch.

And Post Code(s) here


No Start Troubleshooting; "...First thing to check is wiring. Between the large posts of your starter relay (it's not a solenoid) should be a smaller post with a wire attached. This is the wire from your ignition switch through the Park/Neutral Safety Switch (NSS)/Manual Lever Position Sensor (MLPS), Or clutch safety switch on a manual trans, or NSS/MLPS with an AOD/E4OD, to the starter relay and the on to the starter solenoid (if equipped) and starter. Check this wire for cracks, open insulation, or anything that could possibly cause an open circuit. Next, check your upper ignition actuator. Find the ignition rod (on top of the column, running from the steering wheel down to the ignition switch at the base of the column) and make sure it's moving back and forth when you turn the key, through all positions. If it is, your upper actuator is probably not the problem. Lastly, check your ignition switch (again, at the base of the column). Manually push the switch back and forth through the different positions. Push it all the way forward (or down) and see if it will engage the starter. If it does, then your ignition rod is probably bent, which can be remedied quite easily. & If it's an auto, try starting in neutral or while pulling up on the lever while it's in park. If that works, look to the Park/NSS/MLPS. If it's a stick, check the clutch switch. You could try jumping from hot to the small terminal on the starter relay to test it's operation. Sometimes new ones are bad out of the box. If it won't turn over when jumped to the small terminal, you'll know that it's a starter relay issue (Bad part, bad ground or a bad starter. Check to see if da relay is tight to inner fender with no corrosion because the relay's body is ground path via inner fender). If it does turns over jumped to the small terminal, then you'll be looking for something in the small circuit that includes the ignition switch & the park/neutral safety switch (NSS/MLPS) Or clutch safety switch. There should be 12v running from the ignition switch, thru the NSS/MLPS, to the small terminal on the starter relay. Disconnect the small wire to the starter relay (So it doesn't start by surprise, I'd pull the coil wire too). With someone holding the key in the start position, you should be able to read 12v between any point on that small circuit & ground. When you find where you lose 12v, then you'll know where the issue is..."; MIESK5 EDIT; changed a few terms; Also, see Starter (@) Relay Jumping Image in 92-96 @ http://www.broncolinks.com/gallery_images/StarterRelayJumpinin92-96.JPG - Sewiw shows a remote start switch's Jumpers; you can use a small jumper; MIESK5 NOTE; from Ford EVTM; The Control Module (PCM) runs the pump{s} for one second when it receives an ignition- on signal. It also runs the pumps as long as it receives a PIP signal from the Hall-effect devices, it continues pump operation even after the key is released from START. If the PIP signals fall below 120RPM, the control module cuts off the signal to the fuel pump relay or the integrated relay control module. The pump will also run when the terminals of the fuel pump test connector are jumped. the Control module signals the pump when it receives a CRANK signal, and when the Control module gets PIP signals that the engine is running. the pump does not run if the PIP indicates the engine is not running even with ignition ON {except for that first one second}.
Source: by BigUgly88EB and ElKabong (Ken, El Kabong) at FSB


Testing & Diagram at the Diagnostic Link Connector in 84-95; "...Connect FP Relay to any ground to force the fuel pump(s) on when the key is in RUN..." MIESK5 NOTE; from Ford EVTM; The Control Module (PCM) runs the pump{s} for one second when it receives an ignition- on signal. It also runs the pumps as long as it receives a PIP signal from the Hall-effect devices, it continues pump operation even after the key is released from START. If the PIP signals fall below 120RPM, the control module cuts off the signal to the fuel pump relay or the integrated relay control module. The pump will also run when the terminals of the fuel pump test connector are jumped. the Control module signals the pump when it receives a CRANK signal, and when the Control module gets PIP signals that the engine is running. the pump does not run if the PIP indicates the engine is not running even with ignition ON {except for that first one second}.
Diagnostic Link Connectors for EEC-IV processors - 87-95 (black or gray) located under L hood hinge under EEC TEST cover.

Source: by Steve83 (Steve, That dirty old truck) at http://www.supermotors.net/registry/media/245234
 

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Sound good, jopes... I was planning to grab a pressure tester for it in the morning. I'll also pull the spark plugs as you suggested. Should I go ahead and pull each one and check them out while I'm at it or for these purposes just pull one?

Thanks!
The FPR is not very expensive.
A "*******" fix is to give it a good whack with a small hammer or the handle of a screwdriver. Sometimes that shakes things up a bit and it will work for a little while.
IF THE ******* FIX WORKS, go ahead and buy a new one because it will not work for too long but, smacking it is one way of "testing" to see if that is what it actually is.
You did mention that you can hear the pump, right?
Also, press the scrader valve on the fuel rail until it is dry and then turn the key "on" several times.
Ho back and press the valve again and see if fuel comes out.
That is another cheap way of making sure that the pump is getting gas to the rail without going out and buying a pressure gauge.
You SHOULD still have a pressure gauge since you will use it quite often but, for now....
 

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Discussion Starter #6
Nice digitalbill... I like your tips. I didn't get the time to screw with it today but I set aside tomorrow for getting it fixed... hopefully. I also found a nifty $7 spark tester that lets you measure spark strength and I figure I test every spark plug while I'm at it.

Can't thank you enough for the tips... it's lil' tricks such as yours you don't find in the book that can save a lot of time, energy, and frustration! I'll let you know how it goes.
 

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FPR is very cheap. I just had to replace mine on my bronco. The only PITA thing is the screws to hold it down are up side down and you use an allen wrench for them. The easiest way is to get a blanket or towel to lay over the engine and just lay over the engine to get to it.
 

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Discussion Starter #8
So update. I tried the "hillbilly" tricks with no luck. When I pressed the fuel valve on the rail I didn't see gas. I smelt gas for sure but didn't see anything. I'm going to turn the key several more times and try that again and see if I get any liquid.

If not, I hear the pump whine when I turn the key... at least I think I hear the pump. i guess my next step will be to check and ensure I have power at the pump.... if anyone knows a trick let me know. I did check the inertia switch and it is pressed in as it should be.

I'm pretty sure I have spark... but I'm not 1000%. I bought a spark tester and don't see anything... which is weird. Is it possible to have no spark and no fuel at the rail? What would cause this?
 

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splash a couple soda pop cap fulls of gas down the throttle body, see if it fires off. if it does then you have a fuel issue.

My guess would be you have not had a filter changed in a while and the pump took a shit if you have no pressure on the rail.

but you really should put a guage on it and see if it has any with the key cycled.
 

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Discussion Starter #10
Okay... actually I just tried another hillbilly test. While having someone turn the key I checked for fuel at the rail. Oh did it poor... so, fuel pump working. Now I'm wondering if I simply don't have spark. I had bought a spark tester (you're supposed to see a jumped spark from the coil wire to this tester) and I don't see anything. For some reason (cause I terribly question anything I'm unfamiliar with) I'm not confident I'm testing it right. Is there a trick to test spark and know without a doubt whether I'm getting it or not? Will my multimeter be helpful... just don't wanna fry it.

Also, I'm hoping to ensure I understand this correctly, too. If the rail is getting fuel as I just verified it did... that doesn't verify a good FPR, right? That just means fuel is at the rail. Am I correct that the fuel goes to the rail... then to the injectors... what's not used it sent back to the tank via the regulator? So.... hypothetically, it should still start with or without a good FPR???

Thanks
 

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you said you had gas pour out so grab some fans and put them on your engine and blow out all smells/traces/ everything of fuel, when you think youve done that, turn them all off and go to your fpr and take the vacuum hose off and see if you can smell fuel, if you can, the FPR is bad... but again... get a fuel pressure gauge on there as well
 

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Okay... actually I just tried another hillbilly test. While having someone turn the key I checked for fuel at the rail. Oh did it poor... so, fuel pump working. Now I'm wondering if I simply don't have spark. I had bought a spark tester (you're supposed to see a jumped spark from the coil wire to this tester) and I don't see anything. For some reason (cause I terribly question anything I'm unfamiliar with) I'm not confident I'm testing it right. Is there a trick to test spark and know without a doubt whether I'm getting it or not? Will my multimeter be helpful... just don't wanna fry it.

Also, I'm hoping to ensure I understand this correctly, too. If the rail is getting fuel as I just verified it did... that doesn't verify a good FPR, right? That just means fuel is at the rail. Am I correct that the fuel goes to the rail... then to the injectors... what's not used it sent back to the tank via the regulator? So.... hypothetically, it should still start with or without a good FPR???

Thanks
just because your seeing fuel at the fuel rail doesnt mean your getting enuf pressure. you really need a gauge to be sure.

As for spark, having a friend help here would be good. :haha
Using a pair of insulated pliers disconnect a plug wire at the distributor cap and hold it just above the terminal and crank the motor. listen for the click of spark arcing and watch for spark. Now if your pliers aren't very well insulated your buddy will tell ya YA ITS GOT SPARK!!! :rofl:
 

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Okay... actually I just tried another hillbilly test. While having someone turn the key I checked for fuel at the rail. Oh did it poor... so, fuel pump working. Now I'm wondering if I simply don't have spark. I had bought a spark tester (you're supposed to see a jumped spark from the coil wire to this tester) and I don't see anything. For some reason (cause I terribly question anything I'm unfamiliar with) I'm not confident I'm testing it right. Is there a trick to test spark and know without a doubt whether I'm getting it or not? Will my multimeter be helpful... just don't wanna fry it.

Also, I'm hoping to ensure I understand this correctly, too. If the rail is getting fuel as I just verified it did... that doesn't verify a good FPR, right? That just means fuel is at the rail. Am I correct that the fuel goes to the rail... then to the injectors... what's not used it sent back to the tank via the regulator? So.... hypothetically, it should still start with or without a good FPR???

Thanks
Two things.

1: If fuel is getting to the rail BUT the FPR is "wide open" (EG: letting all fuel flow back to the tank), then the fuel injectors might not have the needed pressure to get the fuel into the cylanders.
The fuel injectors are less like a hose and more like a shower head in that it sprays a "mist".
It does this under pressure and if there is not enough pressure then the fuel will not be forced out of the injectors.
One thing that does concern me is that your first press of the schrader valve did not produce anything.
That means that you are losing fuel pressure somewhere along the line.
2: take a capful of gas or some starter fluid and spray it inside of the throttle body. It might start for a second but, that is all you need to confirm if it is fuel or not.
If it starts, coughs, rumbles, or anything else that indicates ignition, change out the FPR.
If there is zero change, look for spark.
Take off a spark plug (whatever is convenient), hook the wire back up and, while holding the plug close to the exhaust manifold, have a buddy crank it over. It is easier to see the spark at night obviously.

Let us know what happens.
 

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Discussion Starter #14
I really appreciate the help, guys. Before reading the latest replies I did pull a brand new spark plug I had laying around and I hooked it directly to the coil wire. I grounded the spark plug and had someone crank the engine. I don't think I'm seeing spark... does it have to be night? I also do smell (lightly) fuel in the vacuum line from the FPR to the manifold. Am I fighting two battles here?

I'm tempted to go grab a new coil... I just feel like I should see spark w/ the above test... then try and see what happens. I'd just feel so much better knowing I'm seeing spark. Opinions? Yes, I'll go ahead and pick up a fuel pressure tester when I run to the parts store.

Is there a way to test the coil further first... or do I bother at this point? Frustrating but I feel like I'm learning.
 

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using the coil wire isnt a good way to test for spark, you should have just used one of the plug wires. using the wire coming from the coil wont give an intermittent spark, plus all you did there is directly grounded the coil and it wont like that.... Does the coil itself feel pretty hot now?? if so its probly a gonner....
 

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Discussion Starter #16
Well... I tested the same thing with a spark plug now... I am not getting anything. I tried testing with my spark tester and I tried holding spark plug next to a tested ground... no good! I did a resistance test on the coil.... I'm not sure if I should test both primary and secondary but primary tested right at .5 ohms and the secondary tested at 7800 ohms. The book first says primary between .3 and 1 ohm... so good there, and secondary between 8k and 10k... short there. But the secondary test appears to only be for Dura Spark Ignitions... mine is TFI IV I believe.
 

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ok, your going to do more damage then good with this engine if you do not do some simple things that have been said.

fuel pressure, check with a proper fuel pressure guage. There is no ******* way to test this.

As Clifton said, you should be checking spark at the plug wires, NOT the coil.

your engine is a basic air pump. Your fuel pump in the tank pushes fuel to the injectors, the Fuel pressure regulator allows the pressure to build up to pressure. Your spark is controlled by the TFI. If you have fried your TFI you will loose spark, your ECM will also not know when to fire off your injectors at this point either.

Put the proper fuel guage on, test fuel, then test spark at the end of the wire where it connects to the plugs. Thats all the testing you really need to do at this point.
 

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PULL CODES! I had nearly the same issue about a month ago...After running completely through the fuel system and replacing FPR, filter, in-line pump, tps, junkyard throttle body, and various other small parts in a effort to nail down the problem, I learned to macgyver codes out of my bronco...turned out to be a bad MAP sensor, a $40 part that took 2 screws, 1 plug, and about 5 minutes to replace. Started on the first try and been running like a dream ever since(probably due to refreshed fuel system lol) The moral of the story is that your problem could be something you never would have thought of. Pulling codes will point you in the right direction...

http://www.fordfuelinjection.com/?p=13

I used a piece of wire and a $3 test light I picked up at the Zone. worked like a charm.
 

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Discussion Starter #19
Okay... I'll try to pull codes again and go get the fuel pressure tester. I didn't get any codes last time (two days ago... it's the first thing I did). I did test spark from each spark plug wire with a spark tester... I'm not seeing spark. Thanks... let you know how to fuel pressure test goes.
 

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FYI: There are NO FAULT CODES for a FPR = fuel pressure regulator, it's a "vaccum" issue so use a fuel pressure gauge to test, the FPR only costs around $23.00...IIRC it's 37psi engine off cranking and 40psi running with the vaccum line disconnected but double check the Haynes Repair Manual or www.broncolinks.com

Good Luck ~ :thumbup
 
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