why do LX and up models have this little hole above each port of the intake manifold, while DX models don't have them? and at the same time they have different injectors with those plastic caps?
and are they interchangeable?
thanks

 

The DX is the only one with the F23A5 engine (non-VTEC) but I don't know what function those little holes are for.

I would not expect the injectors to be interchangeable, but I don't know the specifics.