Home › Forums › Stay Dirty Lounge › Service and Repair Questions Answered Here › 04 gmc envoy 5.3l › Reply To: 04 gmc envoy 5.3l October 13, 2020 at 9:20 am #986691 Richard KirshyParticipant I’m wondering if the MAF is actually functioning at all. Being you stated: ” the maf seems to have no affect on it plugged or unplugged ” and the engine is running on a default strategy. See if these help at all: