I have a 94 Supra NA and I just put on K & N filter and adapter on my car. When I started it up, my car was running rough (vibrating) at idle. Then when I drove it, from about 1,000 to 1,500 rpms it also ran weird. It almost sounds bogged down and vibrates a lot! I rechecked my installation and everything is fastened properly. So I reset my ecu hoping that would be the ticket---I pulled out my ECU fuse while the car was off--- but no such luck.