Help Im Stumped.....Weird Sound?
I have a 99 Ford Ranger Sport Edition V6 4.0. Well In the summer time when my air conditioner is turned on, my engine begins to make a low pitch humming noise and it is really loud. This only happens when my truck is at an idle state like at a stop light. I have put a K&N cold air intake and that seems to be the source of the sound. I took it in to get looked at and the guys said its because my intake is sucking up nothing but hot air causing the noise. This can't be the problem because it did this with my stock air filter as well....So no one seems to be able to help me and i want it fixed because it is really loud and annoying. Anybody know what this is?