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Gallagher99, Senior Vehicle Technician
Category: Ford
Satisfied Customers: 3333
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I have a 2011 Cmax with the 2ltr diesel engine and automatic.

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I have a 2011 Cmax with the 2ltr diesel engine and automatic. Would the lack of an air filter affect the performance of the engine?
Hi there good afternoon to you and sorry for the delayed response
Ok has the air filter been removed or incorrectly installed
Is the engine mangement light coming on with dip in power eveident
Regards ***** *****
Customer: replied 2 years ago.


The air filter was squeezed to fit in its cover and was found to be detached from the inlet flange. The engine management light had come on and there was a big loss of power. A local garage replaced the filter and a sensor and the car has performed fine since. The dealer who carried out the service claims that the badly fitted filter would not have caused the loss of power. Seemed too much of a coincidence to me so I am looking for a second opinion.



Hi john thanks
I suspected this was the isdue as its something we see a lot of in most cases the mil light illuminates intermitently and a dip in power is noticed
This logs a fault code of p003b high air flow or maf (Mass air flow ) circuit too high
The reason behind this is due to an incorrectly fitted or crushed filter
This is down to people being to lazy as all you need to do is remove the 2x8 mm bolts and the air filter outlet pipe pops out. This gives the extra room to correctly fit the filter
There is NO reason to squeeze the filter to get it to fit but people seem to continue to do it
These filters are quite fiddly to fit thus why I always remove the full air box and fit them on a bench so the covers are clipped snug over the filter body thus giving no air leaks etc
If you need anymore help or advice on this issue john please let me know
If you are Completely satisfied with my answer /advice
Kind regards ***** ***** and have a nice day
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