SR20DET CAS failing?
 

Can anyone tell me if they think this is symptoms of a failing cam angle sensor?

I have a 91 Silvia with a blacktop S13 SR. It originally had this hesitation/breaking up issue, and when I put my timing light on the car, it was reading base timing at 0?, so about 15? off. I retimed it to the FSM procedure, it drove great and pulled hard. Next morning, started it and it had the same issue. I put the timing light back on it and it had somehow jumped to ~25?. So I timed it back to 15? again and now it still has the same issue except base timing checks out at 15?.

Is this symptoms of a failing CAS? Or does the CAS just stop working all together when it?s going out? Unless there?s something I?m seriously overlooking, I?m stumped. Thanks!

Cas going bad, a bad harmonic balancer, and loose bolt on the camshaft sprocket. Seen them all cause issue like this