Vtec Solenoid
 

Where is it located on my 98 F23. I want to clean it

Bolted to the back side of the head, near the distributor. Look for the solenoid cylinder sticking up above a 3-bolt flange. There's another 3 bolts holding the spool valve assembly to the head. Get new gaskets since it'll be hardened with age & heat.

Thanks I found it. One more question do I need to take off the top flange and the bottom part. Or just the bottom. It seems kinda tricky to get to the bottom bolts any easy way to get to them. Thanks

Some people just take the whole assembly off of the head & replace it...

You might be able to clean it out without taking the solenoid off the top of the spool valve. If you DO take it off, you'll have to find a gasket for that thing. Honda dealers seem to only sell the whole assembly, not that internal gasket.