Black Beauty has fuel pump electrical issues

[Greg 85]

You are absolutely right! The inertia switch isn't in the coil circuit.

And if you were losing ground at the ECA then it wasn't a circuit problem. But, it wouldn't hurt to make sure this ECA is losing ground as well. And, if so that means something else is causing the problem - unless your new ECA is also bad.

So, while the ground relay at the FPR would work, it would just be covering up the other problem. But at this point maybe you don't care?

That emoji and statement cracked me up! I would really like for the truck to be right, the way it should be. I do not like to place band-aides or rig something to work. However I have had this truck 2-1/2 years and all I do is work on it. I am tired of working on it, I want to drive it and get use out of it. I have spent nearly 2500 in replacement parts, all brand new fuel system, sensors, distributor, IAC, FPR, relays and harness', inertia switch, EAC Ect. Ect. Ect. I am just ready to reap the rewards.

[Gary Lewis]

That emoji and statement cracked me up! I would really like for the truck to be right, the way it should be. I do not like to place band-aides or rig something to work. However I have had this truck 2-1/2 years and all I do is work on it. I am tired of working on it, I want to drive it and get use out of it. I have spent nearly 2500 in replacement parts, all brand new fuel system, sensors, distributor, IAC, FPR, relays and harness', inertia switch, EAC Ect. Ect. Ect. I am just ready to reap the rewards.

I think it is time for a ground relay given all you've been through.

The downside is that the FPR will be pulled in and the pumps running any time the key is in Run. On the trucks like Big Blue there is an oil pressure switch that closes when the engine is running. I don't know if the ECA has safety systems like that, but you'll be bypassing them. So just be aware.

Oh, what about in Start? Will the FPR be pulled in then?

[Greg 85]

I think it is time for a ground relay given all you've been through.

The downside is that the FPR will be pulled in and the pumps running any time the key is in Run. On the trucks like Big Blue there is an oil pressure switch that closes when the engine is running. I don't know if the ECA has safety systems like that, but you'll be bypassing them. So just be aware.

Oh, what about in Start? Will the FPR be pulled in then?

Okay, its been some time. I walked away and came back fresh. Same issue of shutting off after it warms up. Run for an hour or so and shut of. Would restart once cooled. So started digging and testing. I ended up changing the ect sensor and the air charge sensor. No change, so I let it get hot and cut off and I used a 194 to check injector pulse, we have injector pulse. Ohm'd out the injectors and they were 22.8 ohms and around that number on the ones I could reach. As they cooled I continued testing and trying to restart at about 18 ohms the truck was slow to start but a couple cranks it started and ran until hot again. Same test same results. I found some info online, not sure if correct but said the injectors should be between 11 and 14 ohms. Is this correct and am I on to something? What are your thoughts?

[Gary Lewis]

Okay, its been some time. I walked away and came back fresh. Same issue of shutting off after it warms up. Run for an hour or so and shut of. Would restart once cooled. So started digging and testing. I ended up changing the ect sensor and the air charge sensor. No change, so I let it get hot and cut off and I used a 194 to check injector pulse, we have injector pulse. Ohm'd out the injectors and they were 22.8 ohms and around that number on the ones I could reach. As they cooled I continued testing and trying to restart at about 18 ohms the truck was slow to start but a couple cranks it started and ran until hot again. Same test same results. I found some info online, not sure if correct but said the injectors should be between 11 and 14 ohms. Is this correct and am I on to something? What are your thoughts?

Greg - I can't find any reference to the ohm range for injectors in our documentation. But I may be missing it.

What you are saying appears to be that the resistance goes up on them and the truck dies, but when they cool down it'll start? Meanwhile you still have pulses to them, even when it won't start? That doesn't make sense to me.

Do you have spark while it won't start?

[Greg 85]

Greg - I can't find any reference to the ohm range for injectors in our documentation. But I may be missing it.

What you are saying appears to be that the resistance goes up on them and the truck dies, but when they cool down it'll start? Meanwhile you still have pulses to them, even when it won't start? That doesn't make sense to me.

Do you have spark while it won't start?

Yes I have spark even when it wont start, I also have fuel when it won't start. When It does run it seems the resistance increases in the coil for the injector with heat and eventually cuts off at around 22.8 give or take a few tenths. As they cool the resistance drops to around 18 and can start the engine again. Everything I have seen has said 11-14.4 ohms and the high performance injector is like 18 ohms on the high side. Given all the other stuff I have done and replaced, I have never given the injectors a solid look. Honestly because the truck will run. I spoke with a friend of mine who had a very similar problem on a TPI Camaro where he went through and changed the fuel system out, ecm, did all this work and the coils in the injectors were out of parameter. Changed the injectors and the car would run as it should. However this is the only case I have heard of and I am like wth I already have 2500 in parts what is another 350? Tell me what you thoughts are!

[Gary Lewis]

Greg - I can't find any reference to the ohm range for injectors in our documentation. But I may be missing it.

What you are saying appears to be that the resistance goes up on them and the truck dies, but when they cool down it'll start? Meanwhile you still have pulses to them, even when it won't start? That doesn't make sense to me.

Do you have spark while it won't start?

Yes I have spark even when it wont start, I also have fuel when it won't start. When It does run it seems the resistance increases in the coil for the injector with heat and eventually cuts off at around 22.8 give or take a few tenths. As they cool the resistance drops to around 18 and can start the engine again. Everything I have seen has said 11-14.4 ohms and the high performance injector is like 18 ohms on the high side. Given all the other stuff I have done and replaced, I have never given the injectors a solid look. Honestly because the truck will run. I spoke with a friend of mine who had a very similar problem on a TPI Camaro where he went through and changed the fuel system out, ecm, did all this work and the coils in the injectors were out of parameter. Changed the injectors and the car would run as it should. However this is the only case I have heard of and I am like wth I already have 2500 in parts what is another 350? Tell me what you thoughts are!

I'll speculate, but that is all that it is - speculation.

An electromagnet works by the current creating a magnetic field. The more current the more field and, therefore, the stronger the pull is. And fuel injectors are valves with electromagnets in them.

As your injectors are losing resistance they are also losing current. I = E/R, so the current equals the voltage divided by the resistance. The voltage is staying the same but the resistance is changing and so is the current, but inversely.

Perhaps the lower current doesn't create enough magnetic field to open the injector adequately?

Everything I'm reading says that the max resistance is about 17 ohms. So yours have too much resistance.

But I see your reluctance to just swap them out. On Rock Auto injectors for your truck run from $26 to $133 each!

[85lebaront2]

I'll speculate, but that is all that it is - speculation.

An electromagnet works by the current creating a magnetic field. The more current the more field and, therefore, the stronger the pull is. And fuel injectors are valves with electromagnets in them.

As your injectors are losing resistance they are also losing current. I = E/R, so the current equals the voltage divided by the resistance. The voltage is staying the same but the resistance is changing and so is the current, but inversely.

Perhaps the lower current doesn't create enough magnetic field to open the injector adequately?

Everything I'm reading says that the max resistance is about 17 ohms. So yours have too much resistance.

But I see your reluctance to just swap them out. On Rock Auto injectors for your truck run from $26 to $133 each!

Ok, several items, first, Gary, the Ford F1TE-DA injectors (24#/hr, blue top) are 14.4 ohms impedance these are the OEM for the 460, the 302 and 351 engines use an orange top that flows 19#/hr.

Second, on the 1985-86 302 EFI engines, the entire EFI harness grounds through a two flat blade pin plug and socket attached to the battery negative post clamp bolt. The plug and socket are open to underhood conditions and due to their location get a fair amount of fumes from the battery. Corrosion (and high resistance as a result of corrosion) will kill the EFI system. Ford continued to use this on the cars at least through the 1995 Taurus, my 1994 experienced the same type of no start and it ended up being the ground plug for the system. I would unplug and carefully take apart the male pin side and clean the pins then using them and a suitable (PB Blaster is what I use) penetrating oil slide them in and out of the female side.

There is an orange ground wire on the back end of the intake that grounds the O2 sensor input (later models had a 2 wire O2 sensor then went to the heated O2 sensor with 4 wires). If this is broken or disconnected I am not sure what it will do, maybe some rough running but shouldn't kill it completely. The other item, I have seen many of these first gen EFI trucks with absolutely horrible condition harnesses, crumbled insulation, bare wires, green crud in connectors.

If you go to the 1986 EVTM, the injectors are powered and controlled through C160 which should be near where the harness comes through the firewall and should be 4 pins if I remember correctly. The system is basically 2 harnesses, one on the engine, the other runs from the EEC and relays over the left side and front of the engine then to the solenoid valves and MAP sensor behind the battery and ends up at the ground plug.

Here is a picture of the harnesses, injector (engine) portion is on the left:

[Greg 85]

Ok, several items, first, Gary, the Ford F1TE-DA injectors (24#/hr, blue top) are 14.4 ohms impedance these are the OEM for the 460, the 302 and 351 engines use an orange top that flows 19#/hr.

Second, on the 1985-86 302 EFI engines, the entire EFI harness grounds through a two flat blade pin plug and socket attached to the battery negative post clamp bolt. The plug and socket are open to underhood conditions and due to their location get a fair amount of fumes from the battery. Corrosion (and high resistance as a result of corrosion) will kill the EFI system. Ford continued to use this on the cars at least through the 1995 Taurus, my 1994 experienced the same type of no start and it ended up being the ground plug for the system. I would unplug and carefully take apart the male pin side and clean the pins then using them and a suitable (PB Blaster is what I use) penetrating oil slide them in and out of the female side.

There is an orange ground wire on the back end of the intake that grounds the O2 sensor input (later models had a 2 wire O2 sensor then went to the heated O2 sensor with 4 wires). If this is broken or disconnected I am not sure what it will do, maybe some rough running but shouldn't kill it completely. The other item, I have seen many of these first gen EFI trucks with absolutely horrible condition harnesses, crumbled insulation, bare wires, green crud in connectors.

If you go to the 1986 EVTM, the injectors are powered and controlled through C160 which should be near where the harness comes through the firewall and should be 4 pins if I remember correctly. The system is basically 2 harnesses, one on the engine, the other runs from the EEC and relays over the left side and front of the engine then to the solenoid valves and MAP sensor behind the battery and ends up at the ground plug.

Here is a picture of the harnesses, injector (engine) portion is on the left:

http://forum.garysgaragemahal.com/file/n73872/DSCN4036.jpg

So for a 1985 F150 w/5.0L what is the high side ohms for them? also my injectors are black top but that's not to say they are original. Every ground connection has been cleaned and I added more grounds to the system, mainly battery to frame, engine, body and cab. Do you have a part number for the injectors I need so I can ensure I am getting the correct ones?

[85lebaront2]

Ok, several items, first, Gary, the Ford F1TE-DA injectors (24#/hr, blue top) are 14.4 ohms impedance these are the OEM for the 460, the 302 and 351 engines use an orange top that flows 19#/hr.

Second, on the 1985-86 302 EFI engines, the entire EFI harness grounds through a two flat blade pin plug and socket attached to the battery negative post clamp bolt. The plug and socket are open to underhood conditions and due to their location get a fair amount of fumes from the battery. Corrosion (and high resistance as a result of corrosion) will kill the EFI system. Ford continued to use this on the cars at least through the 1995 Taurus, my 1994 experienced the same type of no start and it ended up being the ground plug for the system. I would unplug and carefully take apart the male pin side and clean the pins then using them and a suitable (PB Blaster is what I use) penetrating oil slide them in and out of the female side.

There is an orange ground wire on the back end of the intake that grounds the O2 sensor input (later models had a 2 wire O2 sensor then went to the heated O2 sensor with 4 wires). If this is broken or disconnected I am not sure what it will do, maybe some rough running but shouldn't kill it completely. The other item, I have seen many of these first gen EFI trucks with absolutely horrible condition harnesses, crumbled insulation, bare wires, green crud in connectors.

If you go to the 1986 EVTM, the injectors are powered and controlled through C160 which should be near where the harness comes through the firewall and should be 4 pins if I remember correctly. The system is basically 2 harnesses, one on the engine, the other runs from the EEC and relays over the left side and front of the engine then to the solenoid valves and MAP sensor behind the battery and ends up at the ground plug.

Here is a picture of the harnesses, injector (engine) portion is on the left:

http://forum.garysgaragemahal.com/file/n73872/DSCN4036.jpg

So for a 1985 F150 w/5.0L what is the high side ohms for them? also my injectors are black top but that's not to say they are original. Every ground connection has been cleaned and I added more grounds to the system, mainly battery to frame, engine, body and cab. Do you have a part number for the injectors I need so I can ensure I am getting the correct ones?

Ok, try this link: http://users.erols.com/srweiss/tableifc.htm that is where I got some of the information (at the time I was looking for Chrysler injector information) the resistance I measured on a batch of extra 460 injectors.

[Greg 85]

Ok, try this link: http://users.erols.com/srweiss/tableifc.htm that is where I got some of the information (at the time I was looking for Chrysler injector information) the resistance I measured on a batch of extra 460 injectors.

For future reference, in a case someone else has this issue the Ford #'s are CM4347, E5TZ9F593A, E59E9F593A2B and KM44932 for the injectors on a 1985 Ford F150 5.0L. I ended up ordering Accel brand 24lb injectors from Jegs. My local Ford Dealership said the spec was 24lbs. The injectors I ordered were Accel 150824 and were around $350. Once I get them installed I will update on if that fixed the issue at hand. Thank You all for your assistance in helping me fix this ole Ford!