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My son just purchased a 2013 Ford F250 Powerstroke, 6.7L diesel. It runs fine, no noticeable issues, but I hooked up my scan tool and noticed there's no fuel trim pids. I then searched for 02 sensors and found no pids for them either. I'm quickly learning how little I know about diesels. My plan was to take it on a Flat Rate Test Drive and see how the calculated load, trims, 02's, and injector pw look at varying RPM's, WOT, & cruising. However.... I couldn't select the pids I wanted because they are not there.
How is engine performance and health monitored on diesels? Is there some substitute for fuel trim and 02 sensors?