GMC Envoy owners have reported 1 problem related to power assist brake vacuum hoses, lines/piping, and fittings (under the service brakes category). The most recently reported issues are listed below.
While operating vehicle at about 75 mph in fast lane vehicle lost power, almost causing an accident. Loss of engine power/ steering power, and once vehicle came to a stop. Dashboard illumination showed brake check valve defect.
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all problems of the 2002 GMC Envoy
🔎.