Going nuts here

[Kristie]

Ok so I bought my ex husband's truck its a 97 gmc sierra 5.7 vortec rear wheel drive half ton. he claimed the fly wheel was cracked. Well I have done all the myself on getting this truck going except pulling transmission and putting back in. I've replace flywheel starter, the oil pan gasket, rear main seal, flushed the transmission and put new filter in it. New transmission mount. New carrier bearing. Now he had bought a new distributor cap and rotor. It was the aluminum on. I had issues getting it timed and staying that way. And I would remove the negative battery cable and turn head lights on to reset the timing advance thing. My truck doesn't have the wire you can disconnect. Ok so I ended swapping the the distributor and rotor for one off a parts truck then I am able to get timed. I also want to get this trunning good. Me and my brother use to work on vehicles before he passed so I've been really over the top. I have changed out map sensor that maf sensor new idle air control sensor new throttle position sensor 4 new o2 sensors new fuel pump and fuel filter new pcv valve thing. Ok so the truck now when you start it idles really high then bogs down like it's gonna die then the rpms jumps up again and continues to do this. I filled the take got 155 miles on a full tank so the  gas consumption is out of control my fiance says it's running rich also. I don't know what's wrong with my truck it's only throwing a code p1345 some say vacuum leak other say catalytic converter.... please help

[CamGTP]

That code is for the distributor.

 

https://chevytrucks.org/chevy-p1345-engine-code/