I have a 1986 E350 carbureted 460 engine that has left me stranded. I don't drive the rig very often, and a couple of months ago it died on me while I was driving down the highway in a light load condition. I pulled over, put it in park, and cranked the motor and it started right back up. The other day, I drove about 10 miles and parked and did some shopping (10 Minutes) and came out and the engine cranked but wouldn't start. I bought some starter fluid and sprayed into the air filter and the engine just cranked. I had a friend tow it and as I was towing it I continued to attempt to start with no result. I went out the next day and tried to start it and it fired right up. I checked spark when it wouldn't start and it was not getting any. I did have power to both sides of the coil when it wouldn't start. Any help would be appreciated.

Thanks,
Bill

 

Do you have the TFI ignition module? Sometimes located on the distributor, sometimes on the fender apron. These are failure prone after 70,000 miles or so, give or take 10 years. (?) Usually they fail completely, just as you've pulled on to railroad tracks in front of a fast freight. Sometimes they toy with you a bit.

With no spark, that module is the prime suspect. You can have it tested at some autoparts stores, so previous posts on the subject have said.

 

Not sure about the TFI module. Did not see on the distributor, but will look in the morning. What is the TFI module? Obviously ignition related, what does it do? I am thinking of converting to points....at least I can diagnose and fix the problem.

 

The links here show pics, locations and test info.

Ford Ranger/Bronco II TFI Ignition Diagnostics

Points? Don't be silly.

 

Been there ,done that. Bad distributor.

 

I would expect a worn distributor to run poorly, then quit. Not suddenly quit, then restart after cooldown. That usually points to TFI failure. TFI is about the easiest thing to check at this point.

 

Could be the pickup coil in the distributor. I had this same thing happen with a Duraspark II setup. Intermittent in the pickup coil that would go open when it got hot. Let it sit for half an hour and it would start right back up.

Some troubleshooting will be in order, but you will have to have the multimeter and the diagrams at the ready to be able to test it while the problem exists.

 

Thanks for the info. I printed everything out and will start testing this weekend. Just one note tho, this is not a fuel injected unit but it looks like I can still conduct the tests as described in the TRS link. I won't drive this rig until I get it fixed.

Thanks again,
Bill

 

A 1986 350 should have a Dura Spark II ignition.
If the ignition pickup in the distributor tests good then I would suspect that the blue grommet ignition module is failing.

These are easy to replace.
I would suggest buying a Motorcraft or Napa (Echlin) brand, as many of the Chinese manufactured chain store brands have a very bad reputation.

 

I want to thank everyone for their input and help on this. I went and got a new TFI unit, and the auto parts store sold me the wrong one. I looked at the $40.00 cost of the unit along with figuring the possible cost of a coil and distributor parts and/or complete unit and started talking to my auto parts store friend and decided that GM actually had a better idea and bought an HEI distributor that pops right in. The hassle of working in the engine compartment of a van also factored into my cost/reward decision. After returning the TFI for credit, I got the distributor for $210.00. It also allowed me to clean up some of the wiring and get rid of the coil and TFI. A little expensive, but worth it to me.

Thanks again for all of the input!!

 

Glad to hear you solved your ignition issue Bill!

Let us know how that HEI Dizzy works with hot starts, as I don't believe thay have the cranking retard function of the DuraSpark module.
If you are still set at the proscribed 8* ignition advance I doubt you'll have a slow crank, but I'd like to know.

 

Will do. Spent the afternoon today stripping out the old parts and wiring harnesses that i won't need and I will try and get the new unit in tomorrow and see how it goes. The HEI unit does have mechanical and vacuum advance. Not sure about the retard feature, but i will post an update when I get it back together.

 

It does work; you can see it using a timing light.

I don't think it will matter unless you are running high compression (over 9.0:1). The higher-compression engines are more sensitive to this (I had a 1969 Cadillac 472 and a 1971 429, both of which had 10 to 1 or greater compression).