This bulletin applies to 2015-2021 GMC Canyon vehicles equipped with the LCV engine.
A brake booster vacuum leak may occur noted by an audible hiss noise. DTC C0299 may be stored. This may indicate the vacuum pump leaking oil into the booster.
Inspect the inside of the vacuum hose and booster for a sticky feeling substance on the rubber. If this is present it is an indication that the vacuum pump is leaking oil. Replace the pump and hose, along with the brake booster if needed.
