No spark on 87 suburban? NEED HELP!!!

I have a 1987 suburban that until today ran fine. It was running fine and it just turned off, no spark. I changed the coil and the distributer cap but still no spark. Any thoughts ?

Check the ignition module

it might also be the pick up coil its built into the distributor

i have an 86 shortwide.  ran fine shut it off to change the thermostat and temp sending unit.  wouldn't start. changed the module still nothing.  changed coil and nothing.  changed the pick-up  had the module checked three times and it passed.  Put an older distrubitor that doesn't use a computer and it fired right off.  take the module and get it checked at o'reilly.  My problem might be the computer i took out both possible problems.  more than likely mine is the computer.  

my87burb,   Id definatly start with the ignition module.