just wire the tach up. it doesnt need an adaptor. just wire the power and light for the tach and then ground the black wire.
I've got a 97 2.4 also. If your car came with a stock tach (and it probably did being a 2.4 car) you won't need an adapter. Wire the power wire to a 12v source, the ilumination wire to the dash lights (fuse box, wiring harness), the ground should be abviouse. and finally the tach signal wire. Make sure the tach is set in 4-cylinder mode, and splice or tap the signal wire to the tach signal wire on your ignition modual. I think its the white wire with the blue line, but if you wan't to know for sure, call autometer, lie and tell them you have an autometer tach (doesn't matter if you dont), and they should be able to tell you exeactly where to hook you tach signal wire to, sometimes it's the computer, but I'm pretty sure its on the engine on your car. Just make dang sure before you cut anything. good luck
