Bad Timing Chain? &/Or Cam sensor?

[Roc87]

Still chasing a problem with the GN, after it stalled on Sat. night. Died, cranked, but wouldn't fire. 20 minutes later, started and ran horrilbe, but drove it home. IAC Counts are fine, MAF is fine (swapped with two other good ones to make sure). But I am getting a few degress retard with only 15 pounds of boost, I used to be able to go to 25 with the alky. BLMs at idle are at 90, fuel pressure is 40 line off, and O2 has been swapped with a known good one. Only code the ECM has thrown is bad cam sensor, but I swapped out the cap from a known good sensor. Can the mechanical part of a cam sensor go bad? How can I tell if it's the cam sensor or if the timing chain jumped a tooth??? I've put 40k miles on the car, which had 107k when I bought it (Don't believe it's ever been opened)

 

[Quick6'n'-K.C.]

yes the mechanical part of the interrupter ring can fail-

take the cap off, and check to see if the set pin has failed, and just easily try to spin the ring and see if it spins freely, if it does spin freely, then it needs to be replace, or fixed-

do a compression check to see if its the timing chain, make sure to test with the throttle body OPEN=-


HTH
BW