Bronco_man85 Posted April 23, 2020 Posted April 23, 2020 Hi, just purchased an 86 f150 302 efi from my brother. Few years back we were riding around having no problems, we stop to get gas, and it never cranked up again, I just purchased it from him. Removed the bed to have access to the tank. List of new parts: fuel tank, fuel pump on frame, fuel pump in tank, ignition switch. So my problem is I have no power at the in tank fuel pump connector. I’ve tested the relay. I’m getting power to the inertia switch for a second when I turn the key to the run position. I have power to my level sender but not the pump. Any help is much appreciated
Gary Lewis Posted April 23, 2020 Posted April 23, 2020 Welcome to the forum. However, I was hoping that you would follow what I said in the email I just sent you: Please read the guidelines, below my signature, and then click on this link to say that you agree to adhere to them: I agree to adhere to the guidelines. You will then be taken to the New Members Start Here folder where we ask you to start a new thread/topic in that folder about yourself and your truck. So before we start troubleshooting your Bronco, which we'll be happy to do, please introduce yourself in the New Members Start Here folder.
Bronco_man85 Posted April 24, 2020 Author Posted April 24, 2020 Welcome to the forum. However, I was hoping that you would follow what I said in the email I just sent you: Please read the guidelines, below my signature, and then click on this link to say that you agree to adhere to them: I agree to adhere to the guidelines. You will then be taken to the New Members Start Here folder where we ask you to start a new thread/topic in that folder about yourself and your truck. So before we start troubleshooting your Bronco, which we'll be happy to do, please introduce yourself in the New Members Start Here folder. My apologies I hadn’t checked my emails, I got a bit excited when I was told there was a forum just for bullnose fords
Gary Lewis Posted April 24, 2020 Posted April 24, 2020 My apologies I hadn’t checked my emails, I got a bit excited when I was told there was a forum just for bullnose fords No worries, we'll get there. But, in your intro you said you have three trucks, but you don't have a signature. Having one is highly recommended as if we know the details about your truck we are better able to accurately answer your questions. And speaking of questions, you have one about your '86 w/a 302 and EFI not getting fuel. Assuming it has a single tank (you didn't say and don't have a signature telling ), the schematic below depicts the wiring for your truck. It is from Documentation/Electrical/EVTM/1986 EVTM and then the Electric Fuel Pump Control section. And you have power after the inertia switch? Do you have a pump on the frame, as shown in the schematic? Does it have power?
Bronco_man85 Posted April 24, 2020 Author Posted April 24, 2020 No worries, we'll get there. But, in your intro you said you have three trucks, but you don't have a signature. Having one is highly recommended as if we know the details about your truck we are better able to accurately answer your questions. And speaking of questions, you have one about your '86 w/a 302 and EFI not getting fuel. Assuming it has a single tank (you didn't say and don't have a signature telling ), the schematic below depicts the wiring for your truck. It is from Documentation/Electrical/EVTM/1986 EVTM and then the Electric Fuel Pump Control section. And you have power after the inertia switch? Do you have a pump on the frame, as shown in the schematic? Does it have power? Yes, so it’s a single tank 16.5 gallon. I’ve got power at the eec relay, I’ve got power at the fuel pump relay. I go to the inertia switch and there is power going to it. But when I turn the key to the run position it stays on for about one second, whereas all the previous mentioned connections gave me at least five seconds. Also even if I was to use a jumper I’m only getting 6 volts coming out of the inertia switch where the others gave me anywhere from 10-12. My in tank pump gets no power to the pigtail except to the level sender. I’ve only been able to get this truck running off starter fluid. My frame rail pump is workin. Also my fuel rail has NO Schrader valve.
Gary Lewis Posted April 24, 2020 Posted April 24, 2020 Yes, so it’s a single tank 16.5 gallon. I’ve got power at the eec relay, I’ve got power at the fuel pump relay. I go to the inertia switch and there is power going to it. But when I turn the key to the run position it stays on for about one second, whereas all the previous mentioned connections gave me at least five seconds. Also even if I was to use a jumper I’m only getting 6 volts coming out of the inertia switch where the others gave me anywhere from 10-12. My in tank pump gets no power to the pigtail except to the level sender. I’ve only been able to get this truck running off starter fluid. My frame rail pump is workin. Also my fuel rail has NO Schrader valve. Schrader valves weren't installed on the early EFI systems. I think mid-year '86 is when they arrived. I think. I know you said you have 6v coming out of the inertia switch, but you also said "where the others gave me anywhere from 10-12" and I don't understand what that means. So let's take it one step at a time. Do you have 12v into the inertia switch in Start? If so, do you have 12v out of the inertia switch? That switch should be closed except after a major impact, so you should have exactly the same voltage coming out as going in.
ArdWrknTrk Posted April 24, 2020 Posted April 24, 2020 Yes, so it’s a single tank 16.5 gallon. I’ve got power at the eec relay, I’ve got power at the fuel pump relay. I go to the inertia switch and there is power going to it. But when I turn the key to the run position it stays on for about one second, whereas all the previous mentioned connections gave me at least five seconds. Also even if I was to use a jumper I’m only getting 6 volts coming out of the inertia switch where the others gave me anywhere from 10-12. My in tank pump gets no power to the pigtail except to the level sender. I’ve only been able to get this truck running off starter fluid. My frame rail pump is workin. Also my fuel rail has NO Schrader valve. You're using a digital meter, aren't you? It doesn't have the response time to log the peak of the voltage. The computer won't keep the fuel pump powered unless it is seeing a PIP signal from the distributor. So either the module is bad, the distributor isn't turning (sheared pin, broken gear) or the wiring between distributor & ECM is open somewhere.
Bronco_man85 Posted April 24, 2020 Author Posted April 24, 2020 Schrader valves weren't installed on the early EFI systems. I think mid-year '86 is when they arrived. I think. I know you said you have 6v coming out of the inertia switch, but you also said "where the others gave me anywhere from 10-12" and I don't understand what that means. So let's take it one step at a time. Do you have 12v into the inertia switch in Start? If so, do you have 12v out of the inertia switch? That switch should be closed except after a major impact, so you should have exactly the same voltage coming out as going in. My truck does not have a valve on the fuel line. The 10-12 was the voltage I was reading at the fuel relay and eec relay. I am using a digital multimeter. I’m not 100% sure that the eec is good, I have a friend who is going to bring one out of his truck and as long as the part number is the same I’m going to try it. This was my older brothers truck and he had told my a few years ago that’s what he narrowed it down to. But when I bought the truck from him he said he no longer thought that.
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