FSM states to replace these but is there really any reason? I'll get the crush washers and these if the consensus says to replace, but they aren't cheap. Stock lines still look okay so I am not replacing them yet, just finishing up and getting ready to put the motor back in.

 

They're basically just check valves. You replace them if they're clogged or if oil (air) will flow both ways.

The FSM says to replace a lot of things that don't really need to be replaced.

 

there is a test for them in the FSM, i'm not sure where you are seeing that it merely sais to just up and replace them.

 

Because they can clog up and fail. Test them per the factory service manual. If they fail replace them.

 

When I disassembled my engine, my front rotor housing OMP nozzle was leaking air (air was flowing both ways, and while I do have my Mittyvac, I blew and sucked just like the FSM showed in order to conform to ultimate Mazda inspection standards ).

And that housing had chattering. The engine had not been premixed.

The rear OMP nozzle passed inspection and the rear housing did not have chattering.

Not 100% sure if that's what caused the chattering but I bought a pair of replacements from Mazdatrix to be safe. It was 80-90 bucks w/ shipping.

 

Apparently there was a design change on those injectors..... https://www.rx7club.com/3rd-generati...design-327499/

Also, if you're in there that far, I'd change the OEM lines regardless. Either replace with a new set of OEM lines, a set of stainless lines or IIRC< there was a thread somewhere on making your own replacements with more robust plastic and reusing the old ends.