Are there any cold air intakes compatible 2.4l engine?
Lots of them, http://www.knfilters.com/cold_air_intake/toyota_matrix.aspx ......and many others. Do a Google or Bing or whatever search for a list
Are there any other models of Toyotas or scion cold air intakes that are compatible with the matrix?
A way to find that out is go to one of the on line parts houses, and plug in what you are looking for, the CAI and look at the list of "fits:..."..applications of the particular part. If one supplier dos not list "Fits (whatever) the try another supplier, there are many of them, one or more of them will supply that information.
http://www.ebay.com/itm/Black-Pipe-Blue-Filter-Shortram-Air-Intake-Kit- for-Toyota-09-12-Matrix-2-4L-/310669212632? pt=Motors_Car_Truck_Parts_Accessories&fits=Year%3A2009%7CMake %3AToyota%7CModel%3AMatrix&hash=item485553fbd8&vxp=mtr
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