OK, I kept getting this code, says to replace cam crank sensor, so bought new one, same problem, consistent, I reset code, can drive distance, no engine light, runs fine, but when I shut off and next time I start, engine light is on again and same PO343 code is back. Anything else anyone know which can cause this code?

Thanks,

 

Possible starter. Does it ever crank oddly when you are starting it. A starter with excessive wear can cause a false signal in the RPM sensor circuit as the wires route very close to the starter. I am unfamiliar with PO codes but the volvo code is a ECM-5200.

 

Thanks, but seems to start fine, no strange sounds. Mystery for sure and I can't get inspection updated while check engine light is on.