your speed sensor is failing, the speed sensor is located next to your oil filter it controls your speedometer
there is a problem with your cruise contol,have it checked. also have cam positioning sensor checked
Having the radio in a trick go out while driving can many of things. The most common thing that causes this would be lose wiring.
If you're driving with cruise control engaged and the speed drops while the accelerator pedal continues to press down, it could indicate a malfunction in the cruise control system or a mechanical issue with the throttle. This could be caused by a stuck throttle or a problem with the cruise control actuator. It's important to disengage cruise control and manually control the vehicle to ensure safety. If the problem persists, have the vehicle inspected by a professional mechanic.
when road conditions are bad, slow down your vehicle
There are several things that can cause your 1988 Cutlass supreme to stall out while driving down the road. The most common cause is a malfunctioning fuel pump.
For starters change the fuel filter
your alternator is dead.
It can lead to an accident
slow down before entering and then accelerate while going around
Water Pump or Thermostat. May have to change water pump to replace thermostat.
Change the fuel filter first,
Down and towards the outer edge of the road. Away from the lights.