so last night i was off playing in the mud and when i hit my heater swtich my truck revd up but only when it is on floor and body vents is this a known issue or something new i am sorry if this is posted in the forms some where else thanks for reading

 

What do you mean revs up? On our old truck (Mazda, practically same as the Ford Ranger) the engine would rev up 200rpms or so for a couple seconds and would go back down when we flicked those switches.

 

i revs up and stays up there it is kinda like a high idle and dosent die down

 

Just taking a guess, it doesn't seem that irregular assuming your fan runs off your engine.

 

it has a mec fan on the motor and it only happens on the position for the body and feet

 

could it be a vac line bc my truck only blos heat on cold or out side air at all