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Why is my engine warning light coming on?
If I go over 100kph my revs falter and I get an engine warning light. When it's hooked up at my local garage on the diagnostic tool. The light goes off! No one can figure out what's wrong.
Our answer:
Hi Neil,
That sort of thing is almost impossible to diagnose from afar, I'm afraid. It could be any one of a hundred things, including a blocked DPF filter, dodgy mass air flow meter or crankshaft sensor. However, depending on how modern your car is, I'd expect the reason to show up on a diagnostic machine. Perhaps bring the car to another mechanic for a second opinion?
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