Hello guys,

I posted a msg about 2 months ago about my 1976 f-100 (360 2v) stop running while i drive. This problema had appred to go away when i followed the advice of a member and swapped my coil fwith another (although used). However, in the last 3 weeks the problem has resurfaced. When i am driving along at 50 mph, the rpm drops from 1800 to 1000-1500. THen will temporary go up when i stomp the gas. Only to go back down to 1000-1500, where it will stay for 5-10 seconds and then the engine stops running. Today this happed after driving for 10 minutes, some days it happens after an hour. Also today when i went to give it more gas to try to stop this, the engine backfired. To me that is a spark/timing issue.

After the truck has stopped it will not start for about 10 minutes or so, although today it firedr right up. i am now carrying an old spark plug with me in order to test for spark next time. As this is happening about once a week. I am also going to buy a new pickup coil, because i have a used one on that was suppose to be a temporary fix in October.

Presently i am suspecting the ignition module or pickup coil, not a vapour lock/fuel issue. iu was just wondering if any one else has had a similar issue with there ford, and what was the fix. This probleam is starting to become a real hassle. Any advice would be greatly appreciated.

Thanks guys.

 

I've had ignition modules fail. Normally when they start to go the engine just quit. By the time I'd pulled off the road it would restart. That was the warning things were going bad. If you can pick up a spare module (check the grommet color where the wires comes out to get the correct one) carry it with you. When the problem occurs plug the spare one in and see if the problem persists. I've been advised by my Ford tech to buy these from the dealer as some aftermarket ones are not full featured and carry enough components to start the vehicle but not everything the factory designed. Trust me this guys a tech and not a parts man on commission. He did say some aftermarket ones are legit but it's a crapshoot at best. Hope this may help.

 

hi how ya doin. your heading in the right direction,start with the ignition control module,if it still does it i would go for the distribiter. some trucks in 76 still used points and condenser,or someone could have put a points distribiter in it.(happend to me). on rare occasions the starter soliniod could cause trouble too.(if it uses the terminal marked I for ignition) also check the voltage to the coil, it should be at or under 12volts (9 to 12 volts)(unless coil is internally resisted) an even rarer possability is a wire from the ignition switch that is internally resisted could be bad(been there too) could even be the ignition switch. clean the corrosion out of all the connectors and battery cables. check charging system for over charging if nessessarry. thats about all i can think of electrical wize. the possability of fuel delivery or dirt or water in fuel is still there. if the fuel pump is weak or not pumping enough pressure can cause similar problems. check or replace fuel filters. the older stlye or original fuel pump has the fuel filter mounted on/under the pump(bowl/canister style, unscrew canister to replace filter)(still may have filter at the carb too)not enough fuel can cause back fire.rare possablity is the float in the carb is sticking and not shutting off the fuel coming in and flooding it out, but i dont think its that. check your ignition timing if your to far deadvanced it may cause a problem.perfomance tip, fe blocks (360,390's etc) love to run advanced, about 12 to 14 degrees advanced(btc)if shes stock 12 degrees btc should run good without pinging or hard(slow turn over)starting when hot.hopefully your problem is simple. good luck with the old girl,they dont make them like that no more.
if you couldnt tell i miss my 74. i tore her down to the bare frame and rebuilt her small block 302 to the big block 360 with a C-6 added power brakes and steering redid the wiring harness front to back, yep she was my baby(out ran a few bowties in her day too) till some SOB pulled out in front of me and totaled her. good luck buddy
cdrmckinney's friend jim

 

My 77 did that years ago. I replaced the coil as well. It ran well for a month. Turns out it was the harness to the coil.

 

I noticed no one mentioned vapor lock. Could this be a possibility? I had this problem on my old 78 after changing the fuel pump it still did it. An old mechanic told me to re-route the steel line with rubber away from heat sources. I did the best i could and the problem never resurfaced. BTW be sure the control module when you swap it is grounded I dont know how true it is but i hear they wont work or you can even damage them if you plug them in w/o mounting them to the fenderwell for ground. just my .02 being that i'm only 18 and have a lot to learn

 

I vote ignition module or fuel filter. Check the fuel filter first as it is the cheapest and easiest to change.

 

I definately vote fuel. Spark is to much like a light bulb. Have you ever seen one work partially. Not very often. I say fuel pressure is going away. When you stomp it and get the RPM up it somewhat over comes the problem? I have had several pickup screen issues. The one on the end of the fuel sender in the tank. It gets dirty and sucks flat. Once the truck sits, it opens up and goes fine for awhile. Even a weak fuel pump diaphram is possible. Good luck

 

Hey Whats Up I Have A 1979 Ford I Have Had The Same Thang Happen To Me When The Truck Quick Runing And It Would Not Start It Was The Timeing I Advance The Timeing And It Started Right Up So I Hope That Will Help U .

 

Might be rubber gas line to fuel pump, inside liner gets disbonded and closes up under vacuuum. Reving engine causes backfire or shut down due to fuel starvation. Fuel filter, another suspect.

Good luck,, Ed

 

The same thing happened to my 78 F100. After changing pickup coils, and anything else electrical, I changed the ignition module, and it's been running perfect for the last year.

 

hi. i just had the same problem as you.mine just would die though with no rpm change,my dads scout had a similar prob like yours though. both were ignition related. i changed my igniton module and distributor to a ready to run msd unit and now its great.

 

carry some water with you , next time it starts to happen , pull off the road and feel the ingnition module , if it is hot , pour the water over it to cool it off , if it works , there is your problem , if not , change the fuel filter as suggested . I have had same symptoms with both problems . someone else mentioned to check all the wiring , keep it clean and cool.