94 f350 intermited no spark
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Junior Member
Joined: Dec 2011
Posts: 3
94 f350 intermited no spark
I have a 94 f 350 1 ton with a 7.5 l am having problems with loosing spark some time cold some times hot may run for days then no start at all i have replaced the ignition module and the coil no differance but happening more often now. help any ideas
Senior Member
Joined: Jun 2010
Posts: 16,560
One of the things that could be giving you trouble is the pick up coil in the distributor.
Here is how you can check it, when it won't start.
Using a test lite, at the time the engine won't start ,the lite connected to a good ground, one side of the ignition coil should should have constant voltage whenever the key is on and/ or cranking. The other side of the primary on the coil winding gets the signal from the pick up coil in the dist. and should show a blinking lite when cranking. If the lite doesn't pulsate the pick up coil is defective . Let us know if this helped to solve the problem.
Here is how you can check it, when it won't start.
Using a test lite, at the time the engine won't start ,the lite connected to a good ground, one side of the ignition coil should should have constant voltage whenever the key is on and/ or cranking. The other side of the primary on the coil winding gets the signal from the pick up coil in the dist. and should show a blinking lite when cranking. If the lite doesn't pulsate the pick up coil is defective . Let us know if this helped to solve the problem.
Senior Member
Joined: May 2011
Posts: 717
From: Colorado, near Denver
Of course, I ALWAYS agree with Hanky, as he's ALWAYS right. The close bowl pickup these used did this when they got tempermental. One other thing to check is that these pickup grounded through one of the 2 5.5mm bolts that hold it down. I've seen these get dirty (and corroded) and cause this. Just food for thought.
I hate it when Hanky's always right....
I hate it when Hanky's always right....
Senior Member
Joined: May 2011
Posts: 717
From: Colorado, near Denver
One thing to look out for is the good old fashioned tune up (especially wide plug gap and highly resistive wires) as these put undue stress on the coil, which will shorten its life.
Of course, there is just a really good chance that the coil was at the end of its life, also.
Damn you Hanky, I'll trip you up yet! (I hate to admit it, but you're a good tech. Nice to know there's at least one out there. I might even get you to work on my Escort).
Of course, there is just a really good chance that the coil was at the end of its life, also.
Damn you Hanky, I'll trip you up yet! (I hate to admit it, but you're a good tech. Nice to know there's at least one out there. I might even get you to work on my Escort).
