Ok guys here goes.

I have a 02 GMC 1500 p/u with a 5.3 in it 4wd.

It came in with a skip the check engine light was on with 3 codes

P0101 MAF out of range P0171 Bk #1 lean P0300 random misfire

I checked the MAF elments there fine but I cleaned them any ... Login to read more.