Code P1298 Injector Driver Module Failure
 

1999 F 350, 2 WD 6 speed 7.3 diesel
Out of the blue my truck has started to miss, produces less power and for the first time started to smoke. Grey colored and some light white smoke.
It also displayed a P1298 code.
I was able to do a buzz test on the injectors and all buzzed the same. No difference in sound on any.

Am I looking at a faulty IDM and should I replace it?

Thank you.
Eric