into the coolant reservoir on the passenger side of the engine bay by removing the cap
Any type of antifreeze will work in a 99 Saturn SL1. Many people recommend using Prestone Antifreeze for cars that are older than ten years.
Yes
R-134A
Probably just over a gallon - buy the 50/50 premix and just fill it up
The thermostat on a 1995 Saturn SL1 is located on top of the motor. The largest hose coming off the radiator will have to be loosened to access the thermostat housing on the motor.
Buy a car that isn't a Saturn
Autozone/ advanced auto usually has antifreeze that goes with either kind. I suggest that.
My son's 1999 Salvaged/total Saturn SL1 was rebuilt using many engine and body parts from 1995-1999 Saturn SL1 and SL2 cars, I believe it will work fine. I do not recommend before 1995 or 2000 or later models. I do not recommend SL2 either. I am not the expert but most of my son's engine is not 1999 SL1. Good luck!
12.8 Us gallons
On the 1995 Saturn SL1 The oil pressure sending unit is the sensor closest to the alternator. The unit is on the back of the block.
on the firewall side of the engine below the intake.
Need instructions on how to replace a manual window regulator on drivers side on 1995 saturn