Friends 24 valve knocking?
 

Hi all. I have a friend that has a 24 valve in his dodge that suddenly started knocking while pulling his trailer over a pass. I can hear it's the #4 cyl. It sounds like it's in the top end, as opposed to a rod brng. I'm going to pull the injectors, & have them tested, & put my bore scope in to look @ the cyl walls, & piston. And I'll run the overhead set to look for any valve problems. My questions are:
1- Will my Smarty S06 read any codes in this engine?
2- Are there any known issues that I'm not aware of that I should be looking for?
Thanks. Not familiar with the VP44 system, but I'm certified on the common rail.

Sounds like an injector.

The Smarty pulls codes but I am not sure there is one for a bad injector.
There are ones for the vp but mostly just for voltage and timing issues.

Thanks sixslug. I'm not expecting a code for the injector, but the CEL came on when it happened, but has since gone out, so I want to see what it was. I'm suspecting a blown nozzle, but want to know if there's anything in particular with the VP44 system I should know about.