I have a 2007 caravan with approx 70k miles on it. Recently it has started making an odd noise. It started out happening only after a long drive 2+ hours at highway speeds. It was like a higher pitched sound...like my engine was reving. This was most noticeable when I was stopped and faded or became less noticeable at higher speeds. Now however it is a lot more random and frequent. Some times when wife goes to work in the am it makes this sound and no longer requires a long drive to get it started. Any thoughts?

 

Which engine? Which transmission? "Most noticeable when I was stopped" indicates something in the accessory drive meaning pulleys, serpentine belt, alternator clutch, A/C compressor clutch. If it's in the rear the fuel pump would be suspect.

 

the engine is a 3.3l v6. It is an automatic. I would say the sound is more of a whirring sound not a squealing sound like a loose belt. The sound also seems to be connected with acceleration. I don't think the sound goes away at higher speeds it just becomes less noticeable due to the road noise. The transmission seems to be changing gears smoothly and reverse is fine.

 

That's the trouble with noises. One mans whir is another's squeal. Can you post a video on YouTube and link it here so we can all hear it?

Can you duplicate the noise sitting in your driveway? If yes then use a short length of garden hose cupped to your ear to pinpoint the source. Still can't nail it? Take the serpentine belt of and start it up. Noise gone? You just verified it is something the belt is spinning. If not then I would suspect a spun bearing or cracked flex plate. If you can't hear it in your driveway it may come to waiting till you can or just throwing parts at it. Not an ideal choice but I'd go for the previous.

 

I will try and get a better listen to it this weekend. I will try and record the sound as well....knowing my luck it will run perfectly this weekend.