Car has 46,000 original miles. I've had a new battery installed; new O2 sensor (which is what the computer said I needed); and the pass key fault checked. New ignition installed and new keys made. The car will run beautifully and then last night, driving 55 mph down the highway the car completely dies; lights go out, no power, no dash lights, no emergency flasher lights, nothing. Very scary. It's been doing this since December; it's been towed six times. Car will not restart when it dies, so it gets towed. By the time the mechanic looks at it--the next day--the car starts again. Very frustrating. Must be some sort of electrical problem. I've been assured it's not the alternator or wiring in the ignition. After hours of my own research, I really thought it was the pass key fault causing the problem. But it's been checked and rechecked. HELP. I've gotta unload this thing!

http://impala.homeip.net/impala/faq/impala_faq.html

Q: My Impala has intermittent electrical problems (flickering instruments or lights, engine hesitation or stalling), or the cover to the auxiliary battery connection has melted (near the underhood electrical center). What's up?

A: Under certain conditions, the battery cable connection at the underhood electrical center stud may overheat. This may cause melting of the plastic batter cable cover, the plastic stud housing, or the stud itself, resulting in intermittent loss of vehicle power. This is more likely to occur if extra electrical loads are added to the car. The fix involves moving the terminal, and is coverd in TSB 43-81-48.

Exactly what I was going to say.

Just talked to the mechanic. He says my "power distribution fuse box" is "toast". He's pretty sure this is what has been causing my problems. Does it sound right to you? Thanks. I appreciate your help.

Yes the stud we spoke of is located in that box, it overheats and melts the box. The unlucky have actually had cars catch fire and burn to the ground because of this. One of my wifes former co-workers husband had a 94 Impala she took it to get groceries and while unloading in the garage they notoced smoke, luckily they managed to push it out of the garage before it burned down. Had they not been unloading groceries and seen it and moved the car it would have probably taken their house with it. Bet GM saved less than a penny apiece using a zinc stud as opposed to brass and I bet it is hundreds of cars that have had signifigant damage from this problem.

Thank you so much for your info. Hopefully this repair will be the final one! Appreciate your response.