Odd problem...
 

Earlier today I was coming back from a friends house and stopped to get gas. While filling up I left the key in the ignition to the "On/Accessory" postion to let the radio play. Well after I was done paying I hoped back in and started her up, drove down the road about a half a mile and noticed the Tach jumping all over the place. I immediatly looked at the PFC Commander and it showed a stable 2500RPM while still driving. The car seemed to be driving fine. Well I started to slow for a red light and the car just died, so I coasted it into a parking lot. Shut everything off and tried to crank it up again but the engine just spun and didn't kick over. I turned everything back off and poped the hood looking for any loose lines or anything. Everything looked good. About 3 min later I went to start the car and it started right back up and everything seemed fine(even the tach). Drove it to a friends house then home with no problems. Anyone have any ideas on what happened? I searched , but only found people having problems with bad connections on their tachs causing it to jump around, but their car doesn't die. The only thing I have been suspecting recently is that my plugs are fairly dirty from running rich, but I don't see that messing with the tach like that. Any help is appreciated.

1993 5spd
Non-Seq stock turbos
7k mi on new 3mm, ported engine
Power FC
850 primaries, 1300 secondaries, Nippondenso Fuel Pump
MSD 6A
NGK Racing Plugs

Ive had this happen on one of my other cars.. I wouldent worry about it as long as everything is working fine now.

check the wires going to the leading coil . it happened to me before. BTW, the leading coil is mounted on the driver side fender area, you'll see the spark plug wires comming out of it.

might want to look at the crank sensor wires and connectors. maybe the pfc connections/grounds also. or it could just be that ghost

Thanks Marzooq. I'll take a look at that. Other than this one thing the car is running great and I love it so much! Going to make an appointment with MZM for sometime in May to get everything looked over to ensure that it is 100%.

great. my Mustang should be done within 2 weeks. i got a nitrous kit installed yesterday and the T70 should be on by the end of next week. :D