Got a 2000 honda accord ex vtech automatic transmission idles up and down?

Got a 2000 honda accord ex vtech automatic transmission we been having an idle problem have changed iacv and the tps cleaned throttle body no vacuum leaks and its still making idle rev up and down… What could be causing this? I event as far as checking the timing and everything is fine

Since all Honda's have a problem with tight valves and need to be done every 60,000 miles I'd start with them since hardly anyone adjusts their valves.

You need to locate the diagnostic 2 pin socket (blue) on UK models it's behind the lower centre consul below the ash tray. On the passenger side. Use a jump wire. Turn on the ignition DO NOT START the engine. Which ever warning light on the dash starts to blink that identifies where the problem is. This info is stored on the ecu. Try removing the "radio/back up" fuse for 10 seconds. This clears all fault codes. A possibility is the v tech valve and solenoid. Unscrew the solenoid from the valve. Press the top of the valve for smooth operation. If that's okay. Remove the valve from the cylinder head and ensure the fine mesh filter is clean. If there's dirt on the mesh you will need to use engine flush and do an oil and filter change.