NHTSA Complaint #703845 — 1986 CHEVROLET MONTE CARLO

TRANSMISSION FAILS TO COME OUT OF LOCK UP CAUSING CAR TO STALL AND SHIFT ERRATICALLY WHEN RESTARTED. I FAILURE ANALIZED THE PSOLENOID WHICH WAS REMOVED AND FOUND THE MAL-FUNCTION TO BE CAUSED BY A BLISTERING OF THE PHENALIC CORE MATERIAL DUE TO OVERHEATING THUS CAUSING THE SOLENOID PISTON TO STICK OPEN AND NOT ALLOWING THE FEFLOW OF FLUID TO THE PROPER NON LOCK UP AREAS. I AM NOT ALONE .... THIS IS A FACTORY DESIGN DEFECT IN THE 400 TRANSMISSION. MY SOLUTION WAS TO DECREASE THE POWER ACROSS THE SOLENOID BY 20% BY ADDING A 4 OHM 1 WATT RESISTOR IN THE POWER FEED CIRCUITRY FROM THE NORMALLY CLOSED BRAKE SWITCH POWER FEED. ACTUALLY , GM HAS AN INCORRECT DESIGN HERE AND PERHAPS SHOULD HAVE USED A TEFLON CORE MATERIAL WHICH WOULD NOT HAVE BLISTERED OR HAD A DIFFERENT POWER TYPE UNIT WHICH WOULD NOT HAVE BEEN DEGRADED BY THE HEAT. PROBABLY NOT MANY 96'S AROUND BUT AT OVER A HUNDRED BUCKS A FIX AND POSSIBLE ACCIDENTS .... YOU MIGHT LOOK INTO. THANKS