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Clearing Injector Error P1666

Model: Volkswagen Golf Golf IV, Golf 4, MK 4 - Years: 1997, 1998, 1999, 2000, 2001, 2002, 2003
Part: Warning light – error code

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If at engine start-up the engine runs unevenly (as if running on three cylinders), and the yellow triangle warning light with an arrow illuminates on the dashboard, with error code P1666 present in the engine management fault memory, the fault is likely due to a malfunctioning injector, a common issue with this model.

One repair attempt is to tighten the connector of the wiring harness to the injectors: to perform this repair, remove the rocker cover and gently press the electrical connector attached to each injector without damaging the plastic.

Clear the fault memory and check if the fault reoccurs.


Updated on 12 February 2026 by ScegliAuto


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by ScegliAuto

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