I just replaced the spark plugs in my Suburban, wires also and now I have a P1345 code, I didn't touch the distributor, but hold down bolt was loose, so I assume it could have moved. Question is, I've tried moving the distributor, and have a scantool that tells me it's close too either 0 or 2+-, could the distributor be bad? Or the Cam sensor itself? I'll admit, I'e replaced the distributor on my 96 Tahoe and no issues, spark plugs on my Sub, and a MIL light. How should I approach the issue?

 

Welcome to the forum, I'm guessing you replaced the plugs and wires for a reason? perhaps the condition you were addressing got worse?
I didn't see what year your burb was, but I would suggest replacing the cap and rotor also...
Since you did tighten the hold down I would inspect around that area for any pinched or damaged wires...

 

What I read in the code is crankshaft to camshaft corelation error, in other words the ecm/pcm is saying the two signals are not where they should be in relation to each other. Can you retard the timing to -8 deg? Try that, IF nothing else has changed other than a loose distributor, it could be just that.