Need help on 94 ranger either short or bad alternator or something else

[dean94]

Hello my name is Dean I was driving to work in my 94 ranger 2.3l 5 speed when it died acted like timing belt backfiring and no power then died coasted to exit ramp on side of it. Checked timing still in time changed crank sensor twice. Would only attempt to run for a second or just backfire. Read on here that alternator could be problem had alternator tested after being rebuilt 2 months ago tested bad had rebuilt still no luck had alternator checked and tested bad. Got completely different alternator from jerrys rebuilder that tested good from oriellys. Only time truck will run is when alternator is off truck unhooked or no power to alternator. Even changed fender solenoid due to father in laws advice still no dice tried 2 different battery's still no luck. Checked fuseable link on wire from fender solenoid to alternator and it's good. Left wire off at solenoid truck runs good decided to check and see if voltage was going through the main alternator wire had it had almost 42 volts on that wire.truck runs strong and solid with alternator unhooked just backfires when alternator is hooked only code I have on truck is a engine coolant temp sensor code