I have a 1982 Ford E350 with a 6.6 liter 400 motorhome. It starts up just fine but when it warms up it stalls with no spark. I suspect the emissions control for it is California standards. After it stalls I turn off the switch and turn it back to the Run position and seat belt light does not turn on until it cools . Basically when the light goes on then I usually have spark. Does anybody have any ideas. I have replaced the alternator , the distributor with the pip sensor , duraspark 2 ignition module works I had it tested , new coil, new starter,. I am at a loss thank you for your input do appreciate it.

 

you might check the ignition switch located under the dash, mounted to the steering column and looks like this:
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there is a rod that connects to it which goes up the column to the lock cylinder. When you turn the lock/ignition cylinder, it pulls the rod moving the switch..
My manual for a 1985 E150 says you have to lower the steering column to access the switch.

 

I replaced the switch, forgot to mention that. Same problem still happening..when it does shilut down I turn the switch off then back to the run position and the seatbelt light does not turn on. After a minute or so I try again and the seatbelt light will come on then usually I have spark.

 

Is there anything else not working on the dash when you turn the switch on and have no spark?

Here are some diagrams that might help a little from when i was converting my 85 E150 to a duraspark system. Maybe something on one of them might help.

https://www.ford-trucks.com/forums/1...l#post15241234

I have a EVTM for my 88 E150 and it shows the seat belt circuit feeding off the fuse block from a fuse that receives power only when the ignition switch is turned on.


This is from my 85 E150 showing the seat belt warning buzzer feeding from the ignition switch going through a fuse. This fuse could also be in the fuse block. So we are right back to the ignition switch which feeds the seat belt warning light and power to the DSII module. Perhaps it is a problem before the ignition switch or a ground?

 

I am a bit overloaded on this project... It has baffled a few people now...is there a safety switch somewhere or maybe I can bypass the resistance wire and go straight to the DS ll from the switch.

 

“Basically when the light goes on then I usually have spark.”
Usually or always have spark?

Here’s what I am thinking.. I only have manuals for the 1985 and 1988 E150, and both show the seat belt warning light/buzzer being supplied with power from a circuit that goes through the ignition switch. We know the DSII module power is feed through the ignition switch. If you loose power on both the ignition system and seat belt warning system then it seems like the problem would have to be in the ignition switch or the circuit feeding the ignition switch. You said you changed the ignition switch. Did you check all the terminals in the connector that plugs into the new switch to see if any were burnt?
I would think that if the problem is not at the ignition switch connector, then it is before that circuit reaches the switch. Perhaps a bad connection that gets hot and looses connection. Once cool, it makes connection again.

According to the diagram from the link I posted for you, on the 1983 E150, the circuit that feeds power to the ignition switch, which in turn feeds power to the DSII system in start or run, is a Black with Yellow Stripes #37 on the diagram.
The diagram shows it starting from a fuse link, connecting to the ignition switch at terminal S102, and then continuing on to power distribution.. It is the very top wire on the diagram. IF you connect a test light to that circuit and start the engine, let it warm up till it dies, that would tell you if you have power on that circuit or not when the system fails.
I say to use a test light because digital meters can sometimes show feedbacks as 12 volts.

I think you are either loosing a ground or power to the ignition circuit.

The only safety switch i know of in the circuit is the neutral safety switch and that only prevents you from cranking the engine.
I would think that the ballast wire would be either good or burnt into and not work at all..
According to the 83 diagram, the ballast wire is #16 a 1.1 ohm Red with Green Stripe wire on the drawing and is bypassed by wire 262, a brown wire when in the ignition switch is in the start position. The ignition coil needs full 12 volts while cranking the engine. hense the ballast resister bypass wire. once the engine is running the coil is supplied power through the ballast resistor. If the coil had 12 volts constantly during run, the coil would overheat an burn out.


When it quits do you still have power to the radio, wipers, heater blower, ect. with the ignition switch in the run position?

If you are loosing power at the Black with Yellow Stripes #37feeding the ignition switch, then you could try adding a jumper and see if it starts right back up..

 

OK, the answer is; when the problem happens it does take out that circuit because when I re start the key (turn it off then back into run) the light does not turn on. Takes about 2 - 3 times or maybe 30 seconds before I can get the seatbelt light to go on, however this does not mean I have spark at this time. Now I am beginning to see some kind of pattern and it seems to be temperture related....I do have some confessions. I know enough to be a certified shade tree mechanic. I am basically just trying to isolate the problem. I do not have the resources to get harnesses and special tools, etc. Having said that I have replaced with all new except the switch (it is new but universal) because I wanted to make sure the bar was not doing something. I do believe, after much thought, that it is still wired correctly. Basically the resister wire is on the aux. Because it is open at start, the brown wire on start and the starter solenoid on a push button. So yea I have to turn key to start then push button then when in run all systems the same. I am starting to suspect the coil circuit. My question is the coil that was on it when I bought it and the new one I put on says it has a built in resistor. Does that now make it 2 resistors in the run mode? Now the other night I thought I I found it. Confession # ?....I was not impressed with some harness conditions so I basically wire nutted the connections I did not like...like I said I just want to find and isolate this problem. Well i started it and idled it for a record time. Drove around the parking lot and thought it was good to go. Started it up again and it stalled at the normal timeframe and has ever since... So new coil, distributor (w/pick up coil) cap, rotor, wires, alternator, ...."ignition switch",...


​I have jiggled, wiggled, replaced, cleaned, cussed, and cussed some more. I tell tell ya when it does run it sounds beautiful and starts very nice too. I cannot wait to take it on the open road without worries of blocking the road.
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