Mechanics

SCRAPING WHILE ACCELERATING.

2005 Kia Sedona • 6 cylinder FWD Automatic • 94,000 miles

2005 Kia Sedona: Scraping noise in front drivers side. This does not occur while idling, but only while accelerating. Once it enters overdrive, the scraping noise goes away. It kind of sounds like what brakes do when the pad is gone. When I take my foot off the accelerator, it mostly goes away. If I put it in neutral while moving down the road, the scraping seems to continue.
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Rev_411
February 12, 2011.




BTW, I know this is not a brake issue.


Tiny
Rev_411
Feb 12, 2011.
It sounds like you have at least isolated the problem.

Is the noise concurrent with wheel speed, meaning does it change as speed changes?
Does it change if you put it in neutral while moving and rev the engine up?
How different is the noise under acceleration as opposed to decelerating in gear, and in neutral?

There are a few possibilities; The heat shield for the front passenger brake is bent and touching the rotor. To check this allow the brakes to cool. It is easiest to remove wheel to do this but not necessary. Then feel the area behind the rotor and the heat shield. Feel for contact between shield and rotor. Bend shield till it clears the rotor.

The axle CV joint could be going bad. Signs of this would be vibration under acceleration around 30-40 MPH. Clicking noise when making a sharp turn or U-Turn.


Thanks for your reply.
-The scraping noise is independent from speed. The noise gets louder depending on how much I push on the pedal (again, independent of speed). The volume increases as soon as I press down the pedal, not gradually as the car moves faster (like a brake/rotor sound would occur).

-If I'm moving down the road and put it in neutral, the noise continues, but no longer increases in volume if I press on the pedal, but gets quieter as the vehicle comes to a stop.

-The scraping noise occurs while pushing on the accelerator, goes away for a moment while coasting, but then starts right up again as the car begins to decelerate.

-The transmission is shifting smoothly, and again, the scraping noise is coming from the driver side front (I don't believe that is a transmission component).
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Tiny
Rev_411
Feb 12, 2011.
-Oh, and it completely goes away when the van enters overdrive, which I find really strange. At that point (about 50MPH+), as long as I don't cause the van to downshift, I can push the pedal down and it will gradually accelerate without a scraping noise.


Tiny
Rev_411
Feb 12, 2011.
I think you are right about it being transmission related. The way you analyzed the problem does not leave much room for any other component to be the source of the noise.
Overdrive is sort of, "separate" from the main transmission shafts. That is for lack of a better word. Overdrive is not considered a gear because of this reason. The transmission input shaft is actually turning faster than the engine crankshaft when it is in overdrive. In Drive when in top gear, it is turning at the same speed, not in all cases, and Overdrive is a separate "Unit" to allow the gearing to sort of, "turn around" and get the transmission turning faster than the crankshaft. Sorry for all the quotes, but it is the best way I can explain it. You can even purchase bolt on Over Drives for vehicles that do not come equipped with one.
So, you might try to service the transmission fluid. Use a clean drain pan. When you empty the pan, look at the last little bit of the fluid in the pan and inspect it under a light for metal. That is a sign that you need to rebuild the transmission or at least have it fixed and flushed out thoroughly.
I think you have made my job easy because you have done what I would normally have to walk people through to find out if the noise is related to something that is related to engine speed or road speed or neither. The hard part of this is agreeing with you in that the transmission is the problem. However, since the transmission is not slipping or shifting differently, you might have caught it early enough to at least lengthen its service life or maybe even have it repaired without rebuilding it.
In any case, try changing the fluid and looking for metal or have a repair shop do the same and ask them to save the fluid for your inspection. If you feel that is necessary.

I hope this helps. Let me know how things go and I will keep an eye on this post for your reply.


Thanks again for your reply. I'm having it looked at on Wednesday. I'll keep you posted.


Tiny
Rev_411
Feb 15, 2011.
Goog. Let me know how it goes and I hope the information helped.



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