Inferior CAS?

[B-TownSX]

I was wondering if my CAS is not OEM (s13 sr20det x-type). It doesn't have the two guide dots like the ones on the pics I've seen. I just have one painted on yellow/gold dot. When I do insert the CAS to the block it's positioned at the end of adjustment guide. Sorry I have no pics at the moment. Does anyone know how the SR reads the rpms? does it get the count from the CAS? My tachometer doesn't work and I double checked the wiring (I have DOHC). I thought it might be due to a bad CAS.

[Hijacker]

As far as I know, no aftermarket companies make a CAS for a RWD SR. And I'm trying to remember, but I think some of the CASes I've dealt with had a notch closer to the gear instead of a dot.

As far as the tach goes, the ECU interprets the signal and sends it to the cluster. I believe it's derived from the #1 coil firing, not from the readings off the CAS. But those are all intertwined anyways.

[bruinbear714]

I was wondering if my CAS is not OEM (s13 sr20det x-type). It doesn't have the two guide dots like the ones on the pics I've seen. I just have one painted on yellow/gold dot. When I do insert the CAS to the block it's positioned at the end of adjustment guide. Sorry I have no pics at the moment. Does anyone know how the SR reads the rpms? does it get the count from the CAS? My tachometer doesn't work and I double checked the wiring (I have DOHC). I thought it might be due to a bad CAS.

I havn't seen any CAS other than the factory oem unit. If your tach doesn't work but your engine is running then the problem is the dash wiring from cluster to ecu.

Easy way to check is to pull the cover off and check the trigger disc. There should be 360 small slots and 4 large slots, one bigger than the other.