1999 Honda Odyssey engine dies while driving
 

Our 1999 Honda Odyssey (96,000 miles) has a problem that has the
dealership tech guys somewhat baffled. Recently, we were driving our
van when all the lights on the dash flickered, the engine died and the
green Key light comes on and stays on. We had to put the van back into
park to restart the van. We brought it to our local Honda repair
center. They drove it, but the engine did not fail for them. The tech
told us that his best guess on what is at fault would be a part within
the engine call the Transponder, a device that identifies the keys with
the vehicle or something like that. He ran a diagnostic of the
Transponder and it was found to be working. A new Transponder would
cost $237. I'm not too fond of paying that price for just a guess. The
service rep also suggested having the van towed to the dealership when
the engine fails. I need help with this problem. Could the transponder
show no fault when hooked up to diagnostics, but fail during normal
driving ? What else could be going on ?