Ok, here's the sitch. My 93 is getting no tach reading. Well, sort of. I am getting a regular reading on the Commander, but 0 on the dash tach and 0 on the AVC-R.



This started right after I had the UIM off for work, so I figured I had knocked loose the signal from the coil or worse, knocked off the signal TO the coil and lost trailing fire, so I put on a timing light and got the typical erratic reading from both coils, so I ruled out an ignition problem. Today I had the bright idea to enable the rev reading on the PFC and see what happened and lo and behold, there it was.



The EMS and the AVC-R were both installed by the previous owner, so I have no idea where the signal pick-up is for the tach or boost control. Anyone know off-hand where I should look, or know where I can find a good wiring diagram on the net? I doubt it's just a faulty tach since the boost control is reading 0 as well, but is there a chance that the boost control gets it's signal from the tach itself, rather than just the same source as the tach?



I have yet to get into electrical too much with this car, so I'm pretty ignorant as far as that goes. Any help would be appreciated.

you can download the AVC-R diagram at apexi-usa.com

www.iluvmyrx7.com has the wiring schematics of the car