Chevrolet Repair: 1996 Chevy Diagnostic Code P1345, crankshaft sensor, chevy silverado

Question
Hi CJS. I am currently fixing a 1996 Chevy Silverado 1500 with the 5.7L Vortec motor.  You can disconnect the battery and wipe the diagnostic code off of the computer and then drive it down the road and about a mile down the road it starts to miss like crazy and when you read the code P1345 It does not exactly state what the problem is just tells you to check the connections to the crankshaft sensor and a few others that I do not recall at this time. If you could help me out with this I would really appreciate it. If you need anymore information on this please let me know.  Thanks, Nick

Answer
Hi Nick,

This code is set when either the CAM sensor is not in it's correct position, or when the crank and cam sensor don't agree on position of the pistons.  

These new OBD-II motors are very tempermental and need to run exactly the same all the time.  

Why the code???  Did you do any work on this truck?  Set the timing?  Remove the distributor?  Anything that may have bumped the crank or cam sensor?  Did you go off road in the mud?  Did you have a lot of rain before this happened?  Could this sensor be out of adjustment?  

It could be a connection, or a bad sensor.  Could be a streached timing chain.  Could be a worn cam shaft.  Anything that could cause these two sensors (crank and cam) to not agree.  

If you run bad, it could be the computer trying to compensate for the descrepency between the two sensors.  It could be a real problem, like a misfire or bad timing chain.  

Check your vacuum.  This will tell you if you have out of adjustment chain, or a misfire.

Check your compression.  This will tell you if you have a bad chain, or a problem in a cylinder.

C J S