mine does not have one
I believe they are located on the starter.
inside the radiator hose
It uses a distributorless coil pack and a crankshaft trigger sensor.
Curb weight, 3,309 lbs
inside , right by the drivers right calf, it's hidden behind a pull out panel
The original wheel size is 15"
In the Reatta it is located under the dash next to the steering collum. Silver box has "central power supply" printed on it.
locate the top hose on the radiator drive side follow it back to thermostat housing it's were the clamp is at on the end of the hose.
Regular ethylene glycol antifreeze............
The fuel filter is located near the rear of the vehicle, forward of the fuel tank.
I just purchased a 1990 Buick Riviera with 45,000 on it for my daughter. However, I did have a brief period that you discribed with the car stalling out. I don't know if this will help, but I just read at another site, that it may have a faulty idle air control.