94 Jetta ignition problem, please help!!

I'm recently having issues when starting my mk3 after doing a complete tune up to the car. My only doubt is that I used Neuspeed wires for a Mk2 and they seem to sit just right on the head but when I pull them out they feel loose. I'm not sure if that can be causing my car to backfire and idle when I start it. Once it starts it runs really good but it still backfires. Or could it be a timing issue, please give me your input on this, THANKS!!!

The wires should be okay as long as the pin connectors to the cap & coil were the same. The backfiring could be caused by wiring the plugs to the cap improperly. Cylinder one is nearest the timing belt. If you pull the cap & rotor & dust shield you will see a notch in the rim of the distributor housing , this is # 1, so the plug wire on the cap that aligns with this notch sould go to #1. The firing order is 1-3-4-2 and the distributor turns clockwise as viewed from above so place the wires in the proper order.