Only four months out of warranty, and with less than 20,000 Km on the clock, the owner of this X3 2.0 diesel was not too happy that the engine refused to start, on one wet & windy Monday morning.

He asked me to have a quick look and I discovered a host of codes relating to the electronic EGR valve, including 255C00, indicating a problem with the EGR valve itself.

Further checks revealed that the EGR valve had failed, stuck firmly in the open position. It was this failure that was preventing the engine from firing up. The job time for replacing the valve is under an hour, and mechanically this is quite easy to carry out. He asked me to carry out the job, so I ordered a new unit.

When the replacement EGR Valve arrived, it came with a red warning on the box, indicating that special measures should be taken. These measures are important, and the valve needs to be connected up and powered into the energised position, using diagnostic equipment before fitting. If these measures are not taken, then force may be applied to the valve head during installation, causing damage to the internal drive gears.

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