I have a 1986 G/N and it came up with a "Cam Sensor Failure" Code.It would still run OK but the SES light would stay on all the time. Then with no warning it started Backfiring through the exhaust even when coasting along with no throttle!
I quickly pulled into a parking lot and shut it off. I tried to restart it once and you could hear it binding up and then it would backfire! Is this just the Cam Sensor or possibly the timing chain (stock,with 88,000 miles on it)? Thanks in advance. Curt.
If its having trouble turning over to start, it could very well be a mechanical problem. Chains shouldn't die at 88k, but anything is possible. Might also have had the tensioner for the chain fail. I'd try cranking it over with a breaker bar and socket to see if things are really bound up.
Since you had the cam sensor code, it would be worth having a look at that. Its gear rides on the cam, so anything that let loose under the timing cover might have affected it, too.
I'm guessing these two things happening are more than a coincidence.
I recently changed my valve springs to heavy duty 100 psi springs. Could this factor in?
You could always wipe a cam lobe but I don't see any reason to worry about that until you find out what is going on with the cam sensor. Then I would move to the timing chain.