I have a Focus MK2 ST 2006 with 43K miles. It has ran with no issues but today while driving noticed a loss of power when accelerating, intermittent 'grunt' from engine.
engine oil pressure and temp all good and no unusual noise.
Fuel was low so filled with premium grade but still same. Also noticed the turbo boost pressure flies up when trying to accelerate hard with little difference in power.
Thought maybe coils or injectors as feels like fuel issue but rapid boost pressure fluctuations threw me.
Idles fine and runs fine if not accelerating hard. Not checked anything yet just wondered if anyone has see this before.
Thanks guys in advance for any help.
meant to say engine is totally standard, no maps or mods.