Over lunch I brought my meter home and tested the plugs and the first one (#4) was bad. I already removed it and the filament is broken so it looks like that is the problem. I'm almost positive this happened because I left the key in the run position yesterday afternoon so i could listen to the radio while I cleaned the car out.

My next question is should I replace the plug insulators or just the plugs? I have toyed with the idea of going to the fast glow system but I'm confused as to weather or not I would need a new relay box. The Diesel Giant write up indicated I don't however some posts indicate I do.

Thoughts?