My 2003 gmc v6 just had its plugs and wires and distributor cap and button changed and i put the distributor button on wrong, it ran fine 4 a mon. or 2 and one of the screws came out of the button and wedge it self between the button and the distributor modulator. could it have dammaged the modulator? or whats the problem? it will start up but back fire and die please help josh

The distributor cap and/or the ignition rotor most likely have a crack somewhere and the distributor cap should be replaced along with the ignition rotor. The ignition module could have been damaged as well as the ignition pick-up coil/stator and if replacing the distributor cap and ignition rotor does not solve the problem then the ignition module or the pick-up coil/stator assembly inside of the distributor is also most likely damaged and the distributor will need to be replaced. There is a certain procedure for removing and replacing the distributor, and the ignition timing is not adjustable and it is not set using a timing light or with the engine running, and if you do have to replace the distributor Let me know if you require the procedure to properly remove and replace the distributor or if you require any further assistance.