2500 miles till warranty expires-intense vibrations

[BMGYaris]

hey guys, well, again, I am not talking about my Yaris. It has never had any issues. I just picked up a 2004 Kia sedona, 2500 miles left on the warranty, and I am trying to make sure everything is ok before its gone.


The dealership has been great, even replaced a serpentine belt pulley system for free, even though it wasnt under warranty. That out of the way, I have some strange vibrations that didn't show up when they test drove it, but that show up very regularly under real life conditions (3-8 times per hour). They have checked the bearings, cv, balance, alignment.

At first I noticed the vibrations at 44 mph. I thought i was hitting groves in the road. THen it did it again. Later, I found that if I pass through 1.5rpm or about 2.25 rpm traveling at 44 mph or 69 mph (it has a 5 speed auto transmission...), and occasionally other random speeds, but usually near those speeds, I get intense vibrations.

At first it was everywhere with a loud vibrating bumping sound throughout the chassis. Now it starts in the front, shaking everything including the visors, then the vibration can be heard and felt running down the car, and then the rear of the car sounds like it is riding on the groves along the highway.

I found that when it does it if I level off at a steady RPM with the gas down, but gently and not really accelerating, just enough gas to maintain speed, then it will continue for upwards of 10 seconds or more.

If i let off the gas, it goes away, if I push the gas farther it goes away, if i go up a hill and the rpms change to maintain speed it goes away, if I change speeds but rpms stay the same it goes away. There is some slight variance in the numbers, but it appears to be very consistent.

So, i am imagining either it is the engine mounts, something wrong with the transmission, or the torque/power ratio is not spot on for some reason.

Any better suggestions, or an idea of something to get checked so I can take it elsewhere closer to my house and have them check it?

How much would they probably charge to check the mounts out for me, as those, at least, are still under warranty?

[1NZYaris1]

it could be a varity of things
starting with the plastic covers in the wheel wells or the under car one .
Vibrating with the air movement .
or it could be the Air con pump (Bearing)