I could be wrong, but it sounds like the dealer was trying to make some warranty dollars from MBNA.

The "I was told you should use lower octane by phone" excuse sounds fake. They changed all of your injectors and a coil (was this even necessary?) to run up a huge bill with MB. They then blamed the whole thing on fuel.

I guess it's no big deal for you. You have new injectors and a coil. I'd DEFINATELY keep using high octane fuel.. you have a manual printed by experts on what you should use -- don't risk MB denying you a warranty claim in the future based on what some mechanic told you.

This is not an entirely uncommon thing, by the way

Neal

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