My IKEA FÖRNUFTIG air filter was making a rattling sound, like something had broken off inside. Time to break out the @iFixit tools, and have a go at repairing. First hurdle was the triangle screw driver needed. Which fortunately my tool set has. Then I needed a Philips for a couple more. Finally the spudger to get the top and bottom to part ways (they are clipped together). And with that. I found a small piece is broken off inside.
Reassembly was simple. And it still works
