check engine light on again, and truck in "limp mode". this time it didn't happen when i was driving, happened to my gf on the way to ny. she is going to try to drop it off at dealer in her hometown tomorrow. last week the same thing happened to me i changed fuel filter and air filter and it was fine, all codes cleared after changing the fuel filter. it has gone through a tank of fuel since then. i'm puzzled as to what it could be? bad fuel? or injector troubles? maf sensor? any thoughts on what it could be? truck is all stock.