A lot of people get the wrong idea about servicing and mods.
Firstly you are paying the service department to service your car not inspect it for warrenty mods,and service it is what they will do.
Secondly the air filter is not checked/changed on a first service anyway.
Most dealerships are happy with K&N induction kits as long as you are not requiring warrenty work for an engine problem,K&Ns should not cause a problem but if an engine problem does arise ford will blame the K&N to wriggle out of the claim. Check the guarentee that came with the K&N kit.
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