as in the crank angle sensor for the ecu?? I think the standard ECU runs one on each distributor but I have a wolf V500 ECU and the just uses one of them (hmm, not sure which one). Once i get the replacement coil lead I guess i'll find out
there is an angle sensor on the crank and one on each cam gear, the stock ecu uses the cam gears only for backup and double check. if your useing a aftermarket ecu just set it up to only use the crank sensor if its not already, no big deal.