Hello, bought a ep3 with a 183k mile k20a3. When I purchased the car I thought it felt pretty peppy but almost like the flip of a switch it deffintly feels a lot more sluggish. By no means is it extremely drastic but noticable to me as I drive it every day. I have had acouple different threoys I have tried. I figured maybe vtec wasn't kicking in and it was acting as a 12 valve motor since the k20a3 runs on only one intake valve till about 2200. Tested it with a test light in the car and vtec was kicking in just fine at about 2200ish. At least the solenoids getting power. If I manually activate the solenoid with power at idle I hear no difference in engine tone. Not sure if I should. So not positive yet if the vtec system is at fault yet or not. Another weird thing I noticed was when I manually activate the vtec solenoid with the car off I can here a clicking noise almost solenoid like from under the intake manifold. No clue where that's from. Anyone want to shine some light or maybe a suggestion or too of what to check next?? Thanks

 

Another suggestion I was thinking of was maybe the timing chain had skipped a tooth somewhere but again the car runs great and gets decent gas mileage. Also considering pulling the 02 sensor to check of the cat is possibly clogged because I have had a p0420 code (catalytic converter below threshold) ever so often.

 

Have you checked the plugs or maybe bad gas?