importsmasher

So, my 87 F150 quit on me on my way to work the other day...had to walk 3/4 of a mile....


It lost spark. My first thought was the ignition module....I swapped it for one off of the wife's Mustang (which is currently apart), and still no spark. I have power to the coil; is there a way to test the coil? What about the pickup coil inside the distributor? How do I test that? I don't want to start buying parts and replacing things until I fix it; I would much rather determine what part is defective, and only replace that....It is an 87 F150, 302 automatic, 4x4, if that makes any difference....


Any input is appreciated.


thanks,
Importsmasher

Crownman

Here's a link I found for testing the coil

http://troubleshootmyvehicle.com/for...gnition-coil-1

As far as the pick up coil goes, it's been quite a while since I had to deal with a bad one. BUT, If I remember correctly, if the pickup coil is bad it won't send the signal to initiate the spark, but it can also cause the injector to not fire. So see if the injectors are firing. If they are then I personally would treat the pickup coil as being ok.

also, where did you check to verify no spark?

This is the process I would follow.

Check for spark at the plug end of the wire. Is there spark?
YES - Bad plug
NO - Plug that back in and pull the wire from the distributor and check for spark. Is there spark?
YES - Bad plug wire
NO - Plug that back in and unplug the coil wire from the distributor. Is there spark in that wire?
YES - Bad rotor
NO - Plug it back in and unplug to wire at the coil. Is there spark?
YES - Bad coil wire
NO - Is coil getting power
Yes - Perform coil test posted above
NO - Well, yours is getting power so I'll stop there.

Also, check out this test procedure
http://easyautodiagnostics.com/ford_...d_module_1.php

importsmasher

Thanks, Crownman. All I have done so far is a quick spark test on the side of the road (pull a plug, insert a screwdriver and hold it next to a ground source while cranking the engine), and the aforementioned module swap. I am pretty confident the injectors are firing; I haven't checked them, but you can smell unburned fuel out the exhaust when you crank it over. I will go through the procedure you provided and see where that takes me....


Thanks!


Importsmasher

importsmasher

In case anyone cares, I finally got around to working on the truck....I isolated the problem to the coil, and it runs now that I replaced it.


I have had coils go bad, but usually the engine will miss and run rough; I haven't had one just flat out quit on me before. Is this a common occurrence with these engines?


Thanks for the input.


Importsmasher