| Inspecting throttle valve control unit |
| The idle stabilizer is integrated into the throttle valve control unit. |
| Throttle valve potentiometer, idling switch, throttle valve positioner and throttle valve positioner potentiometer are located in the housing opposite the control cable disc. |
| The housing must not be opened. This means that both potentiometers, the idling switch and the throttle valve positioner are not mechanically set or can be replaced. |
| All settings are performed within the basic adaptation using the -V.A.G 1552-. |
| When de-energized, the throttle valve moves into a specific, mechanically fixed position, which means that the idling speed increases when the engine is warm. |
| The throttle valve positioner takes over the closing damping function of the throttle valve. |
| The throttle valve positioner can only open the throttle valve up to a certain range i.e so that the throttle valve positioner e.g cannot accelerate at “full throttle”. |
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| If the throttle valve control unit is replaced, you must: |
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| Adapt the engine control unit to the throttle valve control unit → Chapter |
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| Earth line between throttle valve control unit and cylinder head o.k → Chapter. |
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| Throttle valve is not damaged or dirty. |
| Special tools and workshop equipment required |
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| Vehicle system tester -V.A.G 1552 - with cable -V.A.G 1551/3- |
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| Handheld multimeter, e.g. -V.A.G 1526 A - |
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| Measuring tool set -V.A.G 1594 A - |
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| Test box -V.A.G 1598/22- |
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