I tow a heavy 5'er and when the Dmax is really working (steep grades) I get a MAF code every time. I reset it when I stop and carry on.

I've erased the code probably 6 or 8 times already. Should I be bringing the truck into a dealer to have this documented ? I've got until 10/28/11 for my 3/36.

Possibly a bad MAF sensor ? Dirty ? (How do you clean the MAF?)


Truck is stock as listed in my signature.

Had the same kind of problems. Ended up being the air filter. NAPA air filter didnt seal up correctly and allowed air the leak by causing the MAF codes.

Change the air filter and see what happens.

I had that happ. Check light came on & power loss before during towing, (I had it in tow haul mode not sure but I dont think it helped it) Had it taken to a stupid GMC dealer in Las Vegas NV they said it was frm a failed DPF cleaning (to much soot.) They cleared it & the next day the Check Light came on took it back now they said it was a EGR & they cleaned it. Next day Light came back on left town with my trailer drove to gallup NM let the truck cool down before I killed it filled up & the light was off. I had the MAF sensor replaced back at my dealer here.