Chrysler Repair: high pitch hum, dodge caravan, high pitch

Question
I just had an oil change and now I hear I high pitch tuning fork type of hum
from underneath my  2003 dodge caravan? What could it be?

Answer
Hi Vicki,
If it started immediately after the oil change, then I would return to where the oil was changed and request that they listen and look for what they might have done/overlooked. Does it happen when you are idling the van or just when in motion?
Try turning the ignition key to the 'run' position with the windows open, but don't try the starter yet. For about a second or so you will hear the fuel pump operate, which often is a humming sound. But it will stop after a second, until you use the starter and get the engine running. It will be less noticeable because of the competing noise. But if the sound is the same as what you are hearing then it is indeed the fuel pump. That is normal. Let me know about what you learn and about the question I asked above.
Roland