Take the 2-minute tour ×  Tonight while driving my 2003 Kia
Sedona with the defroster on, suddenly I heard this very loud
rumbling which sounded like it was coming from the engine
compartment on the passenger side. My first thought was my
exhaust had broken, but as soon as I turned off the heat blower
to listen, the sound went away.  I also smelled something
burning... not quite electrical, maybe rubber.  I pulled over
and checked under the hood, and saw nothing obvious. No fluids
leaking, reservoirs were where they should be, oil was fine,
belts looked in place.  I proceeded to drive home. Once I got
home, while idling in the parking lot, I turned on the heat,
immediately heard the noise, and turned it back off again. In
addition, my dash lights and what not dimmed a bit, as if
something was pulling on the engine pretty hard.  What might the
problem be? Is there a bearing in something that might have
failed?  I don't know if it matters or not, but I was driving
through a light rain around 40 MPH when I first