This is wierd

[silverbullet219]

Hey guys i have a 98 f150 and i've had a weird problem with the truck that noone can diagnose. About six months ago i tripped a code that said i was running lean in bank one. I took it into the dealership and they kept it for a weekend and said they couldnt find anything wrong with it so they cleared the code. About a month later it came back so i went back to the dealership and still they found nothing wrong. Two more months went by and once again it came on again. I have no idea what the problem could be and it doesnt seem to effect the way the truck runs at all. Any ideas?

[LxMan1]

Welcome to the forum.
It's probably either a dirty MAF or a small leak in one of the PCV elbows. It's usually the one the hooks to the rear of the intake manifold.