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ASEMaster35yrs, Master Auto Tech
Category: Classic Car
Satisfied Customers: 2095
Experience:  Master Auto tech since 1972,I own a 65 mustang and have built a 57 ford race car from the bottom up
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Ford F150 Pickup have a 1977 ford f150 w/351, no spark when

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have a 1977 ford f150 w/351, no spark when cranking. replaced all ignition components including the ignition switch, control module, coil, starter solenoid switch, pick-up module, plugs and wires and distributor cap. Any Ideas?

Have voltage to the +side of the coil and -side. Checked continuity of all of the connectors from the coil to the Pick-up assy as well as the connectors to the control module.

Strange phenom - get a spark out of the coil wire when releasing the key from the start postion and again when turning it to the off postion.

The reason I started replacing parts was that the engine would cut out severly while driving and sometimes would die and not restart right away.

The coil says to use with an external resistor but I am not sure of where it is located or if it is a resistor wire. Could this be the problem?
Hook a negative jumper cable from negative on battery to engine ground. Do you have spark now?
Customer: replied 6 years ago.
No, same situation as described above.

When did the problem occur? Did you replace all those parts afterward? What you need to make sure of is the blue/red striped wire is connected to the "S" terminal and yellow wire is connected to the "I" terminal on the relay. The small terminals. Here is a picture: graphic

Since you have voltage at coil+ your resistor wire is fine. What you need to check for now is a flashing pulse at coil- when cranking. If you have your solenoid wires hooked up correctly and there is no flash pulse at coil-, your pick-up or ignition module is defective. You should have 12 volts when cranking and 9 volts when in run position. Tell me more about your symptoms.

Edited by ASEMaster35yrs on 11/11/2010 at 12:08 AM EST
Customer: replied 6 years ago.

The original problem was that the engine stalled out and then would catch and run for a few minutes and then repeat. This was with the original parts. So, I replaced the ignition module, distributor cap & rotor. The engine started and ran but still stalled out (just like shutting off the key) and then would catch again and run. At one time it stalled completely and then would not start but eventually did. At that point, I replaced the rest of the components as described earlier. Now, I get no spark from the coil. Is it possible the the new pick-up is defective? The only component that I did not replace is the reluctor which I have never known them to go bad. (It is just an interuppter) Has me baffled. I think I am going to put the old pick-up back in to test the theroy that maybe the new pick-up module is defective. What do you think? I will be away from my computer for a little while but will leave the site open for your reply, as for some reason, my e-mail address is not being aceptted.

What you are describing to me is a bad ignition switch. When the problem happens, check your voltage readings at the coil + and -. I am almost certain your problem is the ignition switch. Let me know what you find out. What I want to know is when you are cranking, do you have 12 volts on + side of coil and does your voltage pulse on negative side. It is possible there is a break in your resistor wire.

Edited by ASEMaster35yrs on 11/11/2010 at 12:21 AM EST
What you can do is run a wire between straight from battery + to your coil+ and see if it starts. If it doesn't start now, your problem is the ignition module or pick-up. I am assuming your engine cranks over.

Edited by ASEMaster35yrs on 11/11/2010 at 12:33 AM EST
ASEMaster35yrs, Master Auto Tech
Category: Classic Car
Satisfied Customers: 2095
Experience: Master Auto tech since 1972,I own a 65 mustang and have built a 57 ford race car from the bottom up
ASEMaster35yrs and other Classic Car Specialists are ready to help you
Customer: replied 6 years ago.

Yes, it has always cranked. I tried that earlier and it did not have spark at the coil so you must be right, the new pick-up module and/or ignition control module must be defective. I will re-install the old module and see if that works as at least with the original pick-up module, it would start and run albeit cutting out from time to time.


Thanks for you help. I have accepted your answer.


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