Got a tough one. Fair mechanic, but stumped. Have 5.7L GMC suburban with 150K miles, 1999 and has been a great vehicle. Started shifting a bit rough but just threw a code 340 camshaft sensor "communication". So easy fix first replaced camshaft sensor...same code...but fixed amazingly an idle problem I had where wouldn't come down from 12-1500 rpm till full stop?
So then replaced timing chain/sprokets. Another big improvement with now clean tranny shifts and runs great. Old one lots of slack so needed it.
So all good...but still throws code 340 immediately after erasing, many times. Any ideas of next directon or live with it???
thanks all