97 305 vortec p0305 and p1345

[97k1500305]

Hi everyone so I’m getting more codes on my 97 k1500 305 vortec. I just replaced the spark plugs,wires,and distributor cap the other day and I’m still getting codes p0305 and p1345, the truck runs fine no stumble in the rpm’s at idle or at highway speeds. It does kinda shake a little at 45-50 mph but after that it’s smooth again and don’t feel like it’s misfiring at all. I am going to replace the whole distributor tomorrow and retime it with a scan tool and see if that helps but anyone have any ideas?

 

[98 Nitro]

You mentioned a new cap but not a rotor which solved a misfire for me and you need to check cam retard.

 

[97k1500305]

Yeah I replaced just the cap and not the rotor so I’m hoping that is the issue. I am going to replace the whole distributor tomorrow in hopes that it works.

 

[east302]

The cam retard that @98 Nitro mentioned is the usual cause for a P1345 if the distributor has been removed. You’ll need a scanner to set it, so I’d check that before replacing the distributor. Search for “CMP Retard” for the options on getting it set right.

The misfire on #5 may be unrelated.

 

[97k1500305]

The cam retard that @98 Nitro mentioned is the usual cause for a P1345 if the distributor has been removed. You’ll need a scanner to set it, so I’d check that before replacing the distributor. Search for “CMP Retard” for the options on getting it set right.

The misfire on #5 may be unrelated.

It’s weird i have never taken the distributor out I just changed the cap and the code p1345 was coming up before I changed the cap out.

 

[Schurkey]

It’s weird i have never taken the distributor out I just changed the cap and the code p1345 was coming up before I changed the cap out.

Not weird at all.

Distributor gear wear is epidemic on Vortec engines. Coupled to timing chain wear, and P1345 is common. The better "fix" is to replace the gear and replace the timing set as required. But then you still need the scan tool to get the distributor back in correctly.

If #5 is misfiring, do you know that the injector is functioning properly? Does that cylinder have appropriate cranking compression pressure? When were the intake-to-cylinder head gaskets replaced?