Theres a loud rumbling in the front passeger side of the car?

What is your question?

Ok there a rumbling noise in the front passenger side of the car. I kept the car running and popped up the hood but didn't here the noise on the outside of the car. You can only here the noise inside the car. I checked all my pulleys and all the wheels are on wit no play on them. I check the compressor clutch and thats fine too. Now the car only make the noise when the car is ideling. Wheb i put the van in gear and apply gas to it the rumbling stops suddenly and starts to do it again if im at a stop sign or a red light. Can someone help me with this situation please?