E350 wont fire
 

Hi everyone. I have 1994 e350 460 7.5 auto it's a c class motor home. It lost fire .here what did so far.
1 checked for spark with spark plug tester
2 took the ice to the part store it passed.
3 replaced the pick up in the dist,
4 replaced coil
The only test that does pass is the coil wire test for the neg side.
To test the wire you are suppose to use test light put clip on pos side of the battery . Touch the neg wire on coil. And it should flash on and off.
When you turn the key the test light goes dim. And doesn't flash.
But when you unplug the harness from the coil it stays bright but still doesn't flash I'm lost.

No spark? Check the TFI module.