Some 2017-2020 F-150 and 2018-2020 Expedition/Navigator vehicles equipped with a 3.5L EcoBoost engine may exhibit an illuminated malfunction indicator lamp (MIL) with diagnostic trouble code (DTC) P04DB stored in the powertrain control module (PCM). The regulatory monitor for DTC P04DB is sensitive to crankcase system pressure concerns such as oil level indicator o-ring seal, incorrectly installed oil level indicator, crankcase hose, vacuum hose disconnects and oil fill cap o-rings. If root cause is unidentified after inspecting for loose or incorrectly installed crankcase pressure system components, perform Pinpoint Test HG in the Powertrain Control/Emissions Diagnosis (PC/ED) manual.
