Engine warning light and variable valve timing?

An engine warning light on my Ford Focus led to diagnosis of problems with variable valve timing. I have flushed the oil and replaced the intake camshaft oil control valve. The garage suggested a problem with blocked gauze in cylinder head. What are my options?
We think the garage is referring to the brass filter in the oil gallery in the cylinder head.
This can get restricted if the engine has not been serviced regularly and you say that the garage has flushed and changed the oil but no improvement. To clean the filter will require removing the head.

One other thing worth checking is the VVT sprockets as these can also be the problem( we are assuming the fault code is P0017)
Answered by Alan Ross on

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