Testing (On Car): Regulator

Deflate system through service valve and disconnect line at pressure regulator valve. Install a test gauge on regulator valve high pressure line fitting. Inflate system through service valve to maximum available pressure. If pressure is less than 140 psi, start engine to assist in pressure build up. Pressure on test gauge should build up to 100-130 psi and hold steady. Check regulated pressure by momentarily depressing valve core on test gauge. Observe gauge reading. If regulated pressure now reads less than 100 psi or exceeds 130 psi, replace regulator assembly.