My 94 150 has been having an intermitent problem with starting. I would go out to crank it in the morning or after work and it wouldn't start. Give it 15 mins or so and it would start up. Well now its completely done, whatever it is just gave out. I put a spark tester on it and Im gettin absolutely no spark. Its never died while driving, so its not heat related. Any ideas??

 

I've changed three tfi modules in the 18 years I've had my truck, which isn't too bad I guess. The first time the tfi went it wasn't heat related, the truck just quit when I started driving away with the engine still cold. Everytime my truck has quit and had no spark it was the tfi.

 

I agree, I have had Ignition module go out twice on my 89 f150 and once on an 83 Lynx. When they go out, they're out, in my experience they dont work just part of the time.

 

I would guess module as well. Suprisingly enough my 94 still has the origional module (102,000). I was almost tempted to change it just because it is overdue for taking a dump.
However they do fail quite often and can act weird before they go, or they can just quit.
Take it out and have it tested at a parts store. It is free at advance for sure, and probably at most other stores as well.

 

Well I had the module tested twice at two stores each. Its good and i replaced the coil. Still nothing. Next thing Im thinking is the pickup coil in the distributor or possibly the ignition switch? Any ideas on which one should be the first one to change? or is there a way to test either of these? Thanks for the help thus far!

 

Beings that I'm new to trucks in genreal im goign to ask this. What is a tfi module?

 

You might think about checking your cap and rotor as well.

 

This may help.

http://autorepair.about.com/library/a/1g/bl846g.htm

 

You may want to consider our F-150 Firepower Ignition-Click on this link and scroll down:

http://www.performancedistributors.c...50ignition.htm

 

93Sunplex,

Here's a good check to start with. Turn the key on, but don't start the truck. check both coil leads to ground with a volt meter. Either one should have battery voltage on it if the engine isn't turning over. Dunno if it's still the same color codes on the '94's, but if I remember, the green with yellow tracer is the one that's switched by the TFI for spark. If the battery voltage isn't present at the coil, I suspect an ignition switch problem, or a blown fuse. (Yes, this circuit is fused) If I remember what I've seen in the diagrams, the same circuit that feeds the EEC feeds the coil when you turn on the switch. The EEC won't stop the engine from turning over, nor will it interfere with spark during starting. It's very possible you have a dead TFI module, and I read some others that say they've had them fail often. I have a 21 year old T-Bird that still has the same TFI on it in the worst place (on the dizzy right up against the top radiator hose). If there's ever been a TFI subjected to abuse, it's that one, but it still works. Between exploding radiator hoses, heater hoses, etc, that thing has been thoroughly doused with hot coolant more times than I care to remember. The one on my '92 is mounted remotely (which is the case for all post '90 Ford vehicles due to a law-suit) so your '94 should be too. It should be mounted on a large heat sink on the drivers side fender just below the hinge and spring for the hood. Take that out, and get it tested. Do yourself a favor, though, and put it right in front of a heater vent with the heater turned on wide open on your drive to the parts house to get it tested. They can be temperature sensitive, which is what the law-suit/recall was all about. Fords were notorious in the '80s for leaving folks stranded on the side of the road and having their vehicle towed, only to find nothing wrong with it when it got to the dealer. (long enough for the TFI to cool down)

One other thing to check, too. Some of the EEC's would not permit spark until oil pressure is detected. Others just used a delay timer. A tell tail sign that a fuse is blown or a circuit ain't just-so, turn on the key and listen for the 1 second fuel pump test. If you don't hear the pump, the EEC probably isn't getting power either.

 

I think you are more than likely right about the pickup coil in the distributor being bad. It would be very rare for the ICM (TFI) module to be bad. It was common on the distributor mounted ones to fail but you just do not see this happening with the ones on the fender.
Just check the power on the + side of the coil and if you have it in start and run go after the pickup coil in the distributor.
Could also be the coil itself but the pickup coil in the distributor is the most likely.

 

Thanks guys for all the help. I did the test yall talked about, it was good. By process of elimination I decided it was the pick up coil. I went ahead and bought a whole new dist. and now it cranks and runs like a champ. Once again, thanks for the help!!

 

Glad you figured it out. It really sucks when it costs you some $$$$, but at least it is going. This one was a real stumper.