I have 1999 f-150 lightning with 80000 miles
when i'm driving i had the whole truck go dead for about 2 sec. then it comes right back. but every thing just goes dead engine and gages. Its happend 3 times in about 2 weeks. Update Now this is an every day occurrence. I pin pointed it down to when accelerating hard or going over a hard bump. The weird thing is that I can get the radio to glitch on demand by accelerating but nothing else. Still no codes and the battery seems to be fine but haven’t been able to test it under load other then its reading 13.4 v. I think dyotech is right it's a loose wire but where all the bulkhead wire harnesses are tight. Please Help!!!!!

 

Welcome to the site.

Maybe there is an issue with the ignition switch. Something loose in there and when it is dumped the contact that is closed when the truck is on opens up.

 

take a look at your cap and rotor. if the cap is loose it could do that. also smack your streering column with it running and see if that does it. if neither of those are it check all the wires on either side of a few choice harness connectors. if you find a loose wire in there, the connectors are available from dealer for way less than a whole harness. good luckbd

 

I had a car that did this once, the problem in that situation was actually a loose connection at the battery terminals. Id say after you get done checkin what these guys suggested you could always check the battery. After all, a little battery maintenance wont hurt! Good luck!