Need AFM (DoD) info. Is the engine shot? Or is it the AFM issues?

[Supreme Pizza]

 

   2008 GMC Sierra 5.3 that I believe has AFM (DoD)

 

 

    Symptoms: 

 

    Consistent engine tapping / knocking sound when hot or cold. 

    Blows some blue smoke on cold start

    Oil was not changed regularly 

    Unknown oil type in engine 

    Low oil pressure on the gauge 

 

 

    Probably bad rod bearings, maybe the wrist pin. Possibly top end issues. 

 

 

     

 

     Is there any chance that this engine could just have AFM problems, and maybe a plugged screen below the oil sender, or something like that? Or is it shot for sure? 

 

     I guess I should cut the oil filter open and have a look. Maybe there are metal shavings. 

 

     What are your thought? 

 

 

 

 

    

[sefiroxx]

Tapping from one side, one cylinder location?

Tapping: bad lifter, worn rod (valve lash)
Blue smoke: valve seal

[Supreme Pizza]

5 hours ago, sefiroxx said:

Tapping from one side, one cylinder location?

Tapping: bad lifter, worn rod (valve lash)
Blue smoke: valve seal

 

 

Ya, its on one cylinder. Seems to be in the bottom end. And I'm pretty sure you are correct about the valve guide oil seals. 

 

This engine has the standard "Its shot" symptoms, but I was hoping that maybe someone knows of a specific problem with this specific motor that is easy to fix. Maybe something to do with the AFM. 

 

I pretty sure its a paperweight.