Checking the Basic Setting
Checking the basic setting of the charging pressure regulator on the road (basic charging pressure setting)Tools: Pressure gauge 83 93 514
Note: The engine should be at full operating temperature when the basic setting of the charging pressure regulator is checked.
1. Run the hose of the pressure through the hole in the front pillar from the passenger compartment to the engine compartment. Position the pressure gauge vertically to avoid erroneous readings.
2. Connect the hose of the pressure gauge between the connection on the inlet manifold and the hose to the pressure switch.
3. a. Isolate the APC system, by disconnecting the cables to the APC solenoid valve.
b. Alternatively if test loom 83 94 074 is connected (1986 models onwards):
- set knock-detector switch to OFF
- set solenoid-valve switch to OFF.
Note: The engine should be at full operating temperature.
4. Manual transmission. The test should be started in 3rd gear with the engine speed under 1,500 r/min.
Automatic transmission. The test should be started with the gear selector in "1" and engine speed below 1,500 r/min.
5. Depress the accelerator to the floor.
6. When the engine speed approaches 3,000 r/min apply the brakes (keeping the accelerator pressed to the floor) so that the engine is put under full load at 3,000 r/min.
Read off the basic pressure from the pressure gauge.
The basic pressure setting is only the initial setting for the function of the APC system and has no direct effect on the maximum charging pressure level, i.e. engine performance, achieved when the APC system is connected. Engine output is not increased by raising the basic charging pressure above specification.
Maximum charging pressure, which produces the correct maximum output from the engine, is controlled by the function of the APC system.
7. If the basic pressure setting falls outside the specified tolerances adjust as described under 'adjusting the basic pressure of the charging pressure regulator'.
8. If the basic pressure setting falls within the specified tolerances, fit an anti-tamper seal to the control lever stud.
9. Reconnect the cables to the solenoid.
10. Remove the pressure gauge and the APC test loom (where applicable).