One of my regulars asked me if I would connect up his 2004 VW Golf 1.9 TDi to my scanner, in an attempt to try and identify an ongoing problem he had been having. Every now and again, the engine would start to behave in an erratic fashion and the Check Engine light would come on.

The problem would appear to correct itself after a while, and then wouldn’t show up again for normally around a couple of hundred miles. The period between the appearance of the problem was now reducing and so the owner decided that action was need before things progressed further.

The code I read was 18074 - PD Unit Injector; Cylinder 1 (N240): Electrical Malfunction P1666. This was enough to confirm the area of the problem and I suspected that the injector loom which runs through the cylinder head was going to be at fault.

The loom is easy to change on the transverse engine and he decided to not only take my advice, but to also let me do the job.

Once the loom was replaced and the codes cleared, the problem appears to be fixed, hopefully this will be the end of the misfire problems.

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