I just replaced the intake manifold gasket and had a rough running 1997 5.7 engine, I retimed it but now I have a trouble code of P1345 and I can erase it with a code scanner, any one know how to get rid of this code and if it won't go away will it hurt to drive my truck? Thanks

 

Need to set cam offset. Timing has to be 0 degrees at 1000 or so rpms. Need a scan tool to look at engine data while doing this.

 

As acnas stated, the Cam offset or "Camshaft Retard Offset" as GM calls it must be set.
Most inexpensive scan tools cannot perform this function and the timing can only be set with a good scan tool.

I would also start with the basics and be sure the distributor was re-installed correctly

 

had the body shop come with a scan tool and all is well now.
thanks