Diesel in oil - how has this happened? | Ask Honest John

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Diesel in oil - how has this happened?

I had the ‘Engine Malfunction’ warning light on my Ford Mondeo (2008) recently. I took the car to my local dealer and they said it was down to a faulty sensor and reset it. However, the car has now died again and the garage has discovered nine litres of oil in the engine. They say the car is beyond repair.

My question is: how has the diesel got into the oil?

Asked on 25 November 2014 by Ptti Paul

Answered by Honest John

Either because the turbo oil seal failed or because the ECU introduced too much diesel to the engine to actively regenerate the DPF and it failed to burn so simply dribbled down the bores into the sump.

Tags: diesel engines technical issues

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Ford Mondeo (2007 - 2015)

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