Hey I need help! I have a 99 Accord 5sp F23 A1 . Starts up and idles fine runs ok but a little sluggish up to 3800 rpm then falls on its face like a rev limiter or something. I've replaced the knock sensor and vtec solenoid. I changed the oil ,but it was far over due ,but old solenoid wasn't gunked up or anything. I haven't physically tested the new solenoid to prove it engages either. I also have a 2000 Accord that just started doing the same thing. Any help would be appreciated

 

could be a clogged cat, try removing the front oxygen sensor to let it breathe, see if it still does it