jdavidsmi Posted February 24, 2021 Share Posted February 24, 2021 I’m back working on the 86, EFI 5.0 duel tanks, automatic, 2 WD. Got the rear tank back in and the fuel pump ran out of the tank. No fuel to the motor. Started searching wires and circuits to insure I have power. I came across this black/green stripe wire on the right hand side, with the wire cut. Traced the wire, it’s in a bundle that runs from the right of the truck, between the air pump and the alternator. The bundle crosses the motor and into the firewall. It looks like most of the sensor circuits come out of this bundle. I was hoping I would not have to pull the dash apart to follow it further. I’m thinking it’s the eec battery ground and the connector is C101. Page 10 of the 86 EVTM. If so it needs to connect to the battery, could be part of the problem. Thoughts ? Ideas? Link to comment Share on other sites More sharing options...
Gary Lewis Posted February 24, 2021 Share Posted February 24, 2021 Yes, it could certainly be part of the problem. And that looks like the connector right at the battery. Link to comment Share on other sites More sharing options...
jdavidsmi Posted February 26, 2021 Author Share Posted February 26, 2021 Yes, it could certainly be part of the problem. And that looks like the connector right at the battery. Thanks Gary, was not able to look at it yesterday, but I’m going to hook it up and see today. Link to comment Share on other sites More sharing options...
85lebaront2 Posted February 26, 2021 Share Posted February 26, 2021 Thanks Gary, was not able to look at it yesterday, but I’m going to hook it up and see today. C101 is right at the battery negative terminal, if I remember correctly form my son's 86 F150, it is a flat two pin connector that is not sealed and due to it's location right at the battery it is very prone to corroding and losing the ground, the wires are fairly good size, #10 or 12 probably. If it is the problem nothing on the EFI system will work. I was trying to see where a small BK/LG wire near that area would be and it may not even be part of the EFI system. Link to comment Share on other sites More sharing options...
jdavidsmi Posted February 26, 2021 Author Share Posted February 26, 2021 C101 is right at the battery negative terminal, if I remember correctly form my son's 86 F150, it is a flat two pin connector that is not sealed and due to it's location right at the battery it is very prone to corroding and losing the ground, the wires are fairly good size, #10 or 12 probably. If it is the problem nothing on the EFI system will work. I was trying to see where a small BK/LG wire near that area would be and it may not even be part of the EFI system. I connected the wire to the neg side of the battery, and the good news is I now have spark at the spark plugs. It still would not start, and I ran the battery down trying. I still don’t have fuel to the fuel rail. So now back to the second fuel pump, and the tank selector switch. I know the pump in the rear tank works when it was out of the tank. So I’m going to have to figure out how to listen to hear if it runs in the tank. I really don’t know if the switch is the correct one for this truck. It was in a box of parts when I got the truck. I need to study the wiring a bit more. But I’m one more step closer Link to comment Share on other sites More sharing options...
myrl883 Posted February 26, 2021 Share Posted February 26, 2021 I connected the wire to the neg side of the battery, and the good news is I now have spark at the spark plugs. It still would not start, and I ran the battery down trying. I still don’t have fuel to the fuel rail. So now back to the second fuel pump, and the tank selector switch. I know the pump in the rear tank works when it was out of the tank. So I’m going to have to figure out how to listen to hear if it runs in the tank. I really don’t know if the switch is the correct one for this truck. It was in a box of parts when I got the truck. I need to study the wiring a bit more. But I’m one more step closer If the fuel pump(s) aren't running, it's common for the relay to be full of water, dirt, and corrosion. It's on the left side of the firewall, just lateral to the brake booster. Link to comment Share on other sites More sharing options...
jdavidsmi Posted February 28, 2021 Author Share Posted February 28, 2021 If the fuel pump(s) aren't running, it's common for the relay to be full of water, dirt, and corrosion. It's on the left side of the firewall, just lateral to the brake booster. An update , I hooked up my fuel pressure gauge still no fuel pressure, the relay has been replaced, I squirted a small amount of gas into the throttle body and the motor started and ran a few seconds I also found out that I do not have the correct fuel tank selector switch, I have an “A” and a “AA” but I need a “C”. So I will have to find one. Link to comment Share on other sites More sharing options...
jdavidsmi Posted February 28, 2021 Author Share Posted February 28, 2021 An update , I hooked up my fuel pressure gauge still no fuel pressure, the relay has been replaced, I squirted a small amount of gas into the throttle body and the motor started and ran a few seconds I also found out that I do not have the correct fuel tank selector switch, I have an “A” and a “AA” but I need a “C”. So I will have to find one. After looking around on line, I have not found the 9A050-C, anyone know where to find one? Link to comment Share on other sites More sharing options...
Gary Lewis Posted February 28, 2021 Share Posted February 28, 2021 After looking around on line, I have not found the 9A050-C, anyone know where to find one? I think you may be missing something. (Or, maybe it is me that is missing something?) 9A050 is the base part number for a SWITCH ASSY. (FUEL TANK SELECTOR) for any Ford vehicle made anywhere in the world from the mid-1960's until now. And adding the suffix "-C" to it just narrows it down to several million possibilities. What you are missing is the prefix, which will be something like E3TZ or E6TZ, with E3 meaning 1983 as the first use and E6 meaning 1986 as the first use. But an E3TZ 9A050-C is used for the little Ranger truck. And the only 9A050-C that was used for the F-Series was E6TZ 9A050-C and it is only for a 1986 truck. So, can we go back to Square One? Are you looking for the fuel tank selector valve for a 1984 302? Where did you get 9A050-C? Link to comment Share on other sites More sharing options...
jdavidsmi Posted March 1, 2021 Author Share Posted March 1, 2021 I think you may be missing something. (Or, maybe it is me that is missing something?) 9A050 is the base part number for a SWITCH ASSY. (FUEL TANK SELECTOR) for any Ford vehicle made anywhere in the world from the mid-1960's until now. And adding the suffix "-C" to it just narrows it down to several million possibilities. What you are missing is the prefix, which will be something like E3TZ or E6TZ, with E3 meaning 1983 as the first use and E6 meaning 1986 as the first use. But an E3TZ 9A050-C is used for the little Ranger truck. And the only 9A050-C that was used for the F-Series was E6TZ 9A050-C and it is only for a 1986 truck. So, can we go back to Square One? Are you looking for the fuel tank selector valve for a 1984 302? Where did you get 9A050-C? I got the number from the documents, fuel systems wiring, page. Yes you are correct, the switch I need is E6TZ 9A050-C . For a 1996 f150 5.0. Link to comment Share on other sites More sharing options...
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