I finished my projector this afternoon and tested it, and everything was fine. After a 15 minute car ride over to my house, the bulb won't fire up. I can hear the ballast click about every 30 seconds like it did before and the bulb will light up with a blue arc in the inner envelope about every 5 minutes for a second, but even after running it for half an hour, it won't come on. There doesn't appear to be anything physically wrong with the bulb, but then again, I don't know what I'm looking for. Any ideas?

did you let your bulb burn-in for a good long time the first time you started it?

did you leave the bulb in its socket while you transported your projector?

Check all your wiring and re-do any wire nuts.

Unscrew it , bend up the center tab of the mogul, and re-screw it into the mogul.

Also you can lightly shake the bulb , sometimes that works.

I took the bulb out then put it back in and let it run while I was at a Super Bowl party. When I got back, after it had been on for about 2.5 hours, it was on and brighter than ever. To answer your questions, I let it run for about 7 hours the first time it was on and I did leave it in the base while transporting it, which I shouldn't have done.