This Preliminary Information communication provides information to the technician related to vehicles that have a Malfunction Indicator Lamp on. A technician may find Diagnostic Trouble Code P050D set as current or history. The technician is advised to first perform the SI diagnostic. That if the diagnostic fails to isolate the concern, then replace only the exhaust side SHLA's (Stationary Hydraulic Lash Adjuster) and to retest for the concern.
