Vauxhall Workshop Service and Repair Manuals

Test

Work Order Description

Nominal Value

• Ignition ON
• Engine OFF

• Press corresponding key in the system main menu to call up ECU Control Tests, select the desired test and confirm with ENTER . Follow the instructions in the diagnostic tester display.

Note:

The throttle valve positioner can be seen moving between the two end stops

Test okay?

• Engine running at idle speed, operating temperature

• Throttle valve is closed (idle speed)
• Vehicle stationary
• Air conditioning system OFF
• Selector lever in position P/N
• All consumers turned off
• Press corresponding key in the system main menu to call up ECU Control Tests, select the desired test and confirm with ENTER . Follow the instructions in the diagnostic tester display.
• Press corresponding soft key to turn off the injection valves for 3 s sequentially.

Note:

This test helps to analyse engine compression. All fuel injectors are cut-off one after another. Each time an injection valve is cut-off, the engine must move the corresponding piston against the compression pressure. This leads to a reduction in torque and performance, and engine speed drops accordingly. The engine speed reduction must be identical for each injector, since the compression of all cylinders is nearly the same as long as the system is working properly. The electronic control of the engine immediately responds to the disabled cylinder by increasing the injection time of the remaining injectors and by opening the idle air controller. In order to avoid this, the spark angle and the idle air controller position are adjusted to a fixed value. Engine speed is increased to approximately 1200 rpm.

Test okay?