I turned my truck on yesterday and got a check engine light.. i plugged in the OBDII it said P0171 System too lean B1.. i asked a few people + searched on the internet for the causes of this and it said that there maybe an open pipe leading to the intake or i have an exhaust leak or the maf sensor maybe dirty.. i checked for all 3 and everything was fine.. but when i took my maf out i sprayed it with some maf cleaner let it dry put it back again.. when i checked it before cleaning the maf my long fuel trim was quite high about 16-18% at idle i cleaned the maf and im seeing 6-9 percent at idle and when i drive around it adjusts itself goes to negative and back again u think i solved my problem? Cause at idle the short fuel trim goes negative and then goes to different numbers 2-6 but the long fuel trim stays at a constant number 6-9