1991 Ford Tempo Ingnition

Hello I have a ignition problem in a 91 tempo first I start with no spark so I made tests and decide to change ignition module, it work ! I let the car go and 2 hours later they call me and have the same problem tow it back to shop, check it back no spark again so since I just replace ignition module I check for other problems, it looks to be a loose contact between module and pick up signal sensor because it looks to be to old so I replace it, it work ! I let the car go next day call me again tow the car back to
Shop, check it no spark again check module it work check signal to the coil there is signal so I think coil is bad but to make sure I check coil the old way, put my hand on discharge post and it feel discharge but way to low so I replace coil, now I have "spark" but is so so low that don't even arc more than 1/4 of an inch, I will be going to change the coil at parts store (autozone) hope is just a bad coil but I don't really think so, so I need some advice to what to do what else to check on why the module then the pick up signal and then coil what's wrong with this car? Please help