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Home >> Volkswagen >> 2004 >> R32 >> Repair and Diagnosis >> External Pages >> Different car >> Section 14 (1.9L - TDI And TDI Pd Generic Scan Tool, Engine Code(S): ALH, BEW (A4 Platform)) >> 23 Diesel Fuel Injection >> Checking components >> Modulating Piston Displacement Sensor and quantity adjuster, checking >> Notes
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Modulating Piston Displacement Sensor and quantity adjuster, checking: Notes

WARNING: This page does not describe the selected car, but rather 15 other vehicles, including the 2006 Volkswagen Golf, 2005 Volkswagen Jetta, 2005 Volkswagen Golf, 2004 Volkswagen Jetta, and 2004 Volkswagen Golf. However, it is still accessible from the selected car via links, so may be relevant.

Only vehicles with engine code ALH 

The quantity adjuster is an electro-magnetic swiveling positioner which is controlled by the ECM via a directed duty cycle. The eccentric shaft on the quantity adjuster moves the modulating piston on the high pressure piston thereby regulating the quantity of fuel injected.

The modulating piston displacement sensor informs the ECM of the position of Quantity Adjuster -N146- there determines the amount injected.

NOTE: Use only gold-plated terminals when servicing terminals in harness connector to injection pump quantity adjuster.

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