I HAVE A 1987 CHEVY MONTE CARLO LS. RECENTLY IT CUTS OFF WHEN I TURN A CORNER AND WHEN I BACK UP TO PARK. IT DOES NOT SHOW ANY TROUBLE CODES. I CHANGE THE SPARK PLUGS AND CHECKED THE VACCUMS HOSES. WHEN I,M ON THE HIGHWAY,IT DOESN'T SHUT OFF.HAS SOMEBODY HAS THIS PROBLEM BEFORE............

 

I have not, but my '84 Camaro had a time it would randomly shut off AND all electrical shut off with it (no lights, no radio, no nothing) while driving! In that situation, it turned out to be some corroded connections on the starter. Disconnected and cleaned with a wire brush, no more problems.

 

Sounds to me like your ignition switch/and or steering column electrical connections