How to Check the Spring-Activated Coolant Cap on a 1999 Chevy Cavalier

In 1982, Chevrolet changed its lineup, adding its first front-wheel drive vehicle -- the Cavalier. In 1999 -- three years removed from a complete redesign -- Chevrolet equipped the Cavalier with two four-cylinder engine options. The base level engine was a 115-horsepower, 2.2-liter and the optional engine was a 2.4-liter engine that cranked out 150 horsepower. The cooling system in both engines required a holding pressure of 15 psi to raise the boiling point of the coolant. A spring-loaded radiator cap maintains the pressure in the system by releasing pressure if it rises above 15 pounds per square inch. Testing the pressure cap requires a special tool.

Instructions

1

Allow the Cavalier to cool down, if needed, until the radiator cap is cool to the touch. Press down on the cap and slowly twist it counterclockwise to disengage it from the radiator.

2

Pull the radiator cap from the radiator.

3

Set the radiator cap on the open end of the radiator cap pressure-tester. Twist the radiator cap clockwise to tighten it onto the radiator cap tester.

4

Pump the radiator cap plunger until the pressure gauge reaches 16 to 18 psi.

5

Watch for the pressure gauge on the pressure tester to start dropping -- this indicates the cap's purge feature works. Check that the drop in pressure stops at 15 psi, the cooling system's holding pressure.

6

Replace the radiator cap with a new one if it does not hold steady at 15 psi, or does not purge pressure above 15 psi.

7

Remove the old cap from the pressure tester by twisting it counterclockwise. Place the radiator cap -- new or original -- on the radiator filler hole and twist it clockwise to lock it into place.