On a nice day this spring, I switched the ignition module to a popular parts by mail place brand performance replacement TFI module. I did not know how old the old one is, and I wanted to use some ceramic thermal grease before it went bad. When I went to plug the new TFI module in, the top three tabs were a little wider than on the original one, so I had to narrow them with my ignition file to get it to plug in. I tried to just plug it in before I saw the difference. Then I reset the timing and waited for a drier day to test drive it. So the area outside the shop was dry today and the car started right up. But at 2000 rpm, (and it seems to be happening at lower RPMs the longer I run it), the tach needle jumps up and down and the car acts like it has an ignition problem. Koeo code 11, koer codes, 94, 44 (air pump and cat. parts still not hooked up), and 34 (jrichker and I have TRIED to chase this EGR bug down.) I do not see any vac. lines off in the area where I have been looking at the thermactor hole plugs. So do I put the original module back on and drive it to failure and NEVER buy performance parts from this mail order brand again? I doubt it will be warranted as it was hanging on the wall for 2-3 months before I put it in. Should I buy a new one from Ford and keep the old one in my glove box?