944S RPM Not working?
 

Had a 944S2 "roller" that we installed a 944S engine into it (I know - don't ask!). For some reason the RPM tach is not working? I know it worked before - how or what drives it? I assume it's electrical impulse and not cable driven? Any help would be great!! Thanks!!!

944S and S2s use a different wiring harness. You need to look at the wiring down by the ECU and trace the tachometer feed wire as it's part of the engine wire harness that couples up to the body harness. Use the factory wiring diagrams and it's fairly clear. I've done the S2 engine into the S but not the other way round. It is just a case of rewiring one wire.

By ECU you mean the computer under the glove box area floor correct.

Thanks! That makes sense.

Yes, that's what the ECU is. The wire connector of the 944S wire harness that connects to the car, not the ECU, has a pin type multi-plug. The tacho feed wire is in that.