Turbo Boost Pressure Test

Boost Pressure, Check

1. Connect pressure gauge between fuel limiter and intake manifold hose. Place gauge so it can be read from inside vehicle.
2. With engine at normal operating temperature, drive at 1500 RPM in 3rd gear with manual transmission models; 2nd gear with automatic transmission models.
3. Depress throttle pedal to floor for full throttle acceleration. On automatic transmission models, do not depress pedal enough to cause transmission to downshift.
4. On all vehicles, when engine reaches 3000 RPM, apply brakes while keeping throttle pedal depressed and read boost pressure. Pressure should not exceed 10-11 psi. Low boost pressure is not necessarily caused by a turbocharger fault. Refer to ``Troubleshooting.''
5. Reconnect hose to fuel limiter.

Blow-Off Valve, Check

1. Connect pressure gauge between fuel limiter and intake manifold hose. Place gauge so it can be read from inside vehicle.
2. Disconnect electrical connector from blow-off valve. Short connector terminals and turn on ignition to check that instrument panel warning light illuminates.
3. Remove short and reconnect connector to valve.
4. Clamp hose between turbocharger housing and pressure actuator using hose pliers. Do not race engine with pliers clamped on hose as engine could over-rev due to unlimited boost pressure.
5. Drive in 3rd gear on manual transmission models, 2nd gear on automatic transmission models.
6. Carefully apply throttle until engine reaches 3000 RPM while applying brakes. Check that warning light illuminates and blow-off valve opens when pressure gauge reads 11.4-12.1 psi. Do not allow boost pressure to become too high.
7. Remove hose pliers, pressure gauge, and hoses.
8. Reconnect hose to fuel limiter.