Chevrolet Repair: timing, 1996 chevy z71, crankshaft position sensor

Question
I have a 1996 chevy Z71 and i replaced the engine and tranny and since I have had the check engine light on and it gives the code p1345 witch is cam and crank corralation, I've put a new distributor in and changed the crank senser, Ive set the #1 piston to TDC and installed the dis. at the 8 mark on the cap and the code keeps coming back, the truck runs ok but doesnt have as much power as it should and the check light on, I've put a scanner on it and it says it is between -20 and -27 degrees in advance at 1000 RPM Ive been told it should be +or-2 degrees of cam retard. the truck doesnt missfire just feels kinda doggy.
Ive tried to install distributor like the book says and it still gives the code p1345 do you know what they mean by line the mark up with the pre-drilled holes in the distributor I've tried this and the rotor bug is off the 8 mark and the truck misses. but everything I read tells you to set these and there is no adjustment in the distributor, if you can help it would be very helpful.

Thanks

Victor

Answer
Hi Victor,

I checked my shop manual and the proper code identification for a P1345 is "Crankshaft position sensor / Camshaft position sensor correlation". Same code for both and it either is malfunctioning or needs adjustment.
To drop a distributor, use a timing light on #1 cylinder and make note of the timing, then put the pick-up on #4 ( having a brain fart on this but it will be the 5th cylinder in the firing order). Make note of the mark. You may also have to disconnect the PCM timing connector located under the floor mat on the passenger side under the dash. It will be a 5/16" black connector with a small brown or beige wire.
You should have a scan tool to set the distributor correctly. You can get the engine to tdc on the compression stroke of cylinder #1 and check where the rotor is pointing in the distributor. It should be pointing at a "V" shaped pointer with an 8 on it in the distributor housing, if it isn't turn it so it does line up with the 8.

There have been some issues with distributor gear wear that could cause this too.


Here is a story from someone else:

I just went through this on my 97 GMC Suburban. My son and I replaced the leaking intake manifold gaskets and marked the distributor very well to get it back in the same position. The crank was not moved while the distributor was out. We dropped it back in and lined up our marks like it was when we removed it, and when it fired up the SES light was on all the time. It didn't seem to run quite right, idled ok but didn't seem as zippy as before we worked on it. The mechanic said the distributor was off slightly so it wasn't timed right but the cam sensor was bad also. He said there is a mark on the balancer and another one (a "V") on the timing chain cover and these have to be lined up when #1 is at TDC. Then there is a "8" mark on the distributor that has to line up with the pointer on the rotor and a mark on the intake. He said the cam sensor was bad because he couldn't get it any closer than -17 degrees and it's supposed to be 0 deg. plus or minus 2. Runs great now. I think the key is having the scanner that will read live stream data, but I don't have the 4K to buy one of those. BTW, the cam sensor is in the distributor and the crank sensor is in the front of the oil pan on the right side behind the balancer. Good luck with yours.

I want to make sure you realize to disconnect the connector that puts the motor in basic timing mode.  

Hope this helps.

C J S