Boost Pressure

To check boost pressure of turbocharger system, use Pressure Gauge (VW 1397). Gauge is equipped with a valve to lock pressure measurement.
CAUTION: This test requires a chassis dynamometer. If dynamometer is not available, testing can be simulated with a road test.
Remove kick panel from right side of footwell. Remove hose from vacuum port on Ignition Control Unit (ICU). Attach gauge between vacuum port and previously removed hose. Open gauge shutoff valve.
Warm engine until oil temperature is greater than 176°F (80°C). At 35 MPH, fully open throttle in second gear (A/T) or third gear (M/T). When vehicle reaches 55 MPH, close gauge shutoff valve.
NOTE: On vehicles with A/T, DO NOT allow transmission to downshift during test procedure.
Boost pressure readings will vary with altitude. See BOOST PRESSURE SPECIFICATIONS table. If boost pressure readings are as specified but driveability problems remain, check fuel system.
If boost pressure readings are not as specified in table, replace wastegate and retest. If readings are still out of specifications, replace turbocharger.

BOOST PRESSURE SPECIFICATIONS