Need help with a problem. I have a stock 1969 GTO with the 400 engine. The car has been redtored for 8 years now and I have just started having a proble this season that is confusing. It starts and runs great as always, the problem is that after driving for awhile (time varies) it will just die. All the power seems to shut down(no dome light, ignition, etc.). After it sits for a minute or so the power comes back and the car starts right up and we are on our way. The battery still has power when the car shuts down like this. I ran it in the driveway and pulled and wiggled wires thinking I might find the problem, but nothing did it. I keep running through the system in my head and can not think of what would cause this. Any suggestions would be helpful.  

i have been thinking about this... my thoughts are dirty or loose connections at the top post on the starter solenoid.    loose ground wires to the body and the engine block.

check that the 2 screws that hold the fuse block to the firewall are in from the inside... when the fuse block is not bolted tight to the firewall it can disconnect the wiring harness on the engine side of the firewall. (been there done that in my 66 GTO a long time ago)

unplug the engine compartment harnesses from the bulkhead connector and examine the terminal for signs of heat and melting of individual terminals in the connector block..   it will probably be a red wire... replacement terminals are available or you can extract that single wire from both sides of the connector... and if you don't care what it looks like too much... use a european style terminal block (from radio shack) section with a piece of 10 or 12 gauge wire passing through after you install the both sides...  this removes the quick disconnect and uses the european style terminal block to connect it tight enough to pass the amperage you need... and still be easily removable and reuseable without needed to cut and strip more wire if you have to disconnect the bulkhead connector later...

it is more than likely at the bulkhead connector.. as that is one of the few points that would take out everything.. and it might come back....

i looked up a wiring diagram... it should be a thicker red wire on one of the corners of the engine side connector... look carefully... they are packed with black grease so it might look ok... buts it's not...    it feeds both the ignition switch and the head light switch...  

If the above post doesn't fix your issue look to the ign switch to need ajusting or replacing. Also make sure the cable/plug is fully seated in the switch.