TheMAN
06-23-2009, 03:58 PM
Starting in 2005 in the US, the SP23 models came equipped with a cabin air filter for the HVAC system. This feature was further expanded to most Mazda3 models in 2006 (for all of North America).
Most SP23s (built between November 29, 2004 through May 1, 2005) came with a different cabin filter than the 2006 models (some SP23s were built until May 16, 2005 and will use the newer style filter). These filters are different in that they have an air defuser glued into the upper filter. This was intended to redirect and slow the air flow to the evaporator due to a prevalent concern at that time about lack of cooling from the A/C experienced in the 2004 models (which did not have cabin filters in North America).
A TSB countermeasure part was released for the (early) 2004 models to be installed to slow down the incoming air and distribute it evenly to the evaporator so that the air could be cooled down better. This part consisted of a piece of air defuser installed where the cabin filter would normally go. Obviously, it is possible to install a cabin filter in lieu of the defuser plates. Some time in mid-2004 (I believe July 2004 IIRC), these defuser plates were installed from the factory until May 1, 2005 when all Mazda3s started using the larger Mazda5 evaporator core.
So ever since then because of the larger Mazda5 evaporator unit being used, the defusers were no longer necessary regardless of whether the car came with a cabin filter or not.
pics are attached to illustrate the differences. The parts are all interchangeable and obviously you can exchange the parts for another one to change the desired results
also shown is how the defuser greatly affects how the air flow goes through it... you can see the dark spots in the filter pleats where the defuser holes are and the rest of it is clean because they were blocked!
http://www.torontomazda3.ca/forum/picture.php?albumid=171&pictureid=887
http://www.torontomazda3.ca/forum/picture.php?albumid=171&pictureid=888
http://www.torontomazda3.ca/forum/picture.php?albumid=171&pictureid=889
Most SP23s (built between November 29, 2004 through May 1, 2005) came with a different cabin filter than the 2006 models (some SP23s were built until May 16, 2005 and will use the newer style filter). These filters are different in that they have an air defuser glued into the upper filter. This was intended to redirect and slow the air flow to the evaporator due to a prevalent concern at that time about lack of cooling from the A/C experienced in the 2004 models (which did not have cabin filters in North America).
A TSB countermeasure part was released for the (early) 2004 models to be installed to slow down the incoming air and distribute it evenly to the evaporator so that the air could be cooled down better. This part consisted of a piece of air defuser installed where the cabin filter would normally go. Obviously, it is possible to install a cabin filter in lieu of the defuser plates. Some time in mid-2004 (I believe July 2004 IIRC), these defuser plates were installed from the factory until May 1, 2005 when all Mazda3s started using the larger Mazda5 evaporator core.
So ever since then because of the larger Mazda5 evaporator unit being used, the defusers were no longer necessary regardless of whether the car came with a cabin filter or not.
pics are attached to illustrate the differences. The parts are all interchangeable and obviously you can exchange the parts for another one to change the desired results
also shown is how the defuser greatly affects how the air flow goes through it... you can see the dark spots in the filter pleats where the defuser holes are and the rest of it is clean because they were blocked!
http://www.torontomazda3.ca/forum/picture.php?albumid=171&pictureid=887
http://www.torontomazda3.ca/forum/picture.php?albumid=171&pictureid=888
http://www.torontomazda3.ca/forum/picture.php?albumid=171&pictureid=889