p0101 code

2008 H&S delete with AFE intake. Wife was driving truck last week and check engine light came on. I checked for a code on my tuner and found P0101. I pulled the MAF. It did not look dirty but cleaned it anyways with CRC MAF cleaner. Pulled the battery negatives to clear code and cleared code on H&S. Started up motor, no code and let it run for about 1 minute at idle. This morning I went out and as soon as I started it the engine light came on ??????????????? Truck runs fine. The tuner and cai has been on for several months with no problems.
Any suggestions?