The owner of this car had noticed a lack of power lately, and was sure his 2006 BMW 520D was not performing as it used to. The BMW had just over 90,000 miles on the clock and should have still had a lot of life left in the motor.

When the customer arrived at my door, I took the car for a quick run and could immediately feel that it certainly wasn’t pulling its weight and as the old saying goes, it wouldn’t pull the skin off a rice pudding.

I checked for codes in the ECU, and found none. I moved on to look at the mechanical problems that may have occurred, starting with the turbo. I found the impeller to be sticking. Instead of spinning freely and delivering a boost of air to the engine, it was actually acting as an obstruction in the induction system.

The turbo needed to be replaced. Along with the turbo, the oil feed pipe and oil return pipes needed to be checked and cleaned. I also ensured that the oil feed supply was good and that this wasn’t the cause of the initial failure.

Once the new turbo was in place and the oil pipes had been primed, the engine was started and allowed to tick over for a short while before setting off on a test drive. Once on the road, the difference was easily noticeable and the customer was very happy to get the power restored.

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