Do 1998's have this valve
My 1998 civic had a low idle so I cleaned the throttle body and the air idle sensor. The fast-idle thermo valve is my problem. I can not locate this part?
that depends what engine your Honda has. If the engine number (check your metal tag inside the engine compartment) starts with a D(16Y8 etc.) than it does not. D type engine did not use those after 1996. So to completely answer this we will need more information.