My 1998 Buick Lesabre will be running fine and then all of a sudden stop showing mph and completely lose power. I can pull it over and start it again if I press hard on the gas pedal and drive off really quickly. Some days this will not happen at all, other days five or six times. Do you know what could be wrong?
[b]If the speedometer suddenly stops working when this happens, it indicates that there’s a problem with the Vehicle Speed Sensor signal. If the engine management system loses the VSS signal, it loses one of the major inputs to the engine and transmission operations.
My 2000 lesabre was just fixed 8-24. The Mass Air Sensor on my car was cracked and in moist weather the MAS would cause me to lose the engine. I would go to neutral, hit the starter and then back to drive. This problem started the middle of June. The car did not show any error codes until 8-24. The car was driven 15 miles in damp weather. I tried to get it to run with a normal idle 3 hours later - no luck. Had the car towed in by AAA. The computer showed a MAS error zero time ago. The MAS housing had 3 cracks leading to the center of the MAS case. It may have been cracked by a technician or by driving 13 hours highway speed in hot weather in June. The MAS unit has a very hot wire in it to do its job. See my question “2000 buick lasabe - engine stops when car is coasting”