You should check the pick-up coil, it can short out the modules. I have ran into this problem before and was a the end of my rope. I found a pamphlet at the auto parts store and read through it and came to the conclusion that the pick-up coil was shot, replaced it and never had to put another module in.
Probably lack of die electric grease under the mounting surface of the module. This special grease keeps the module cool & lack of it could cause the module to overheat & burn out.
The 1991 Blazer has a current draw causing the wire to burn. You will need to trace the wiring out to find what is drawing too much current.
GO BUY A NEW IGNITION SWITCH AND KEY SET TO INSTALL IN THE COLUMN. It's not that simple smart#@$! If anyone can answer the question intelligently I would appreciate it.
It sounds as if you have a bad ignition control module. It would be located on the distributor. On some of these vehicles, the module was moved over on to the side of the left fender. Ford had a lawsuit against them for these modules, but the time to submit claims against them has expired. It is also referred to as the thick film ignition (TFI)module.
Pull out eack spark plug individually, the one that's not working will look wet or oilly. It will look wet because the gasoline is not burning completely or at all. That would be the ignition coil to replace.
Check your local library, they may have a auto repair database that would have wiring diagrams, ours does.
Ignition switches and body control modules are issues on these cars.
Make sure there is the correct voltage going to the dist. On yours I think you should have about 8 volts not 12. There should be a resistor wire to cut the voltage down. Probably lack of die electric grease under the mounting surface of the module. This special grease keeps the module cool & lack of it could cause the module to overheat & burn out.
The 1991 Blazer has a current draw causing the wire to burn. You will need to trace the wiring out to find what is drawing too much current.
Ignition module in the distributor.
A bad ignition module.
It would have electronic ignition, no points.
test ignition coil,ignition module,pick-up coil,electronic spark control,and knock sensor
I would expect that the power for the fuel pump would be supplied through the ignition switch so I would start there, that is check the ignition switch.
I would suspect a failing ignition control module.
Probably ignition switch. Have it checked out.
I would replace the ignition control module that's in the distributor.
Because it has HEI (High Energy Ignition).