Boost Pressure
- Before checking supercharger boost pressure, ensure engine idle speed is correct. See ADJUSTMENTS article. Ensure engine oil temperature is 176°F (80°C). Check knock sensor operation. See KNOCK SENSOR under IDLE CONTROL SYSTEM in this article.
- Connect Pressure Gauge (VW1397) or equivalent to the pressure regulator hose using adapter "T". Open pressure gauge check valve to position "A" and start engine.
- Remove harness connector from CO potentiometer and Blue connector from temperature sensor (in front flange on cylinder head). Accelerate to full throttle. Engine speed must increase periodically then drop (surge). Watch pressure gauge, boost pressure must reach 8.7 psi (0.6 kg/cm2 ). If boost does not reach specification, check for leaks in air system and correct by-pass valve setting. Check supercharger.