Will a k&n aftermarket intake make my car shut off
No, but if it as over oiled it could have dirty the MAF element and make it idle poorly. You can eliminate this condition by cleaning it with CRC MAF cleaner. Check www.youtube.com for a video on how to do it.
if it's properly installed, it will not cause any malfunctions. most common is user error in over-oiling the filter.
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