2002 Sonata V6 GLS Rapid Accel/Decel Problem

[RolandDeschain]

I just bought a 2002 Sonata V6 GLS automatic this past Monday (11/27/06) and everything was peachy. Earlier tonight (Thursday) on my drive home (less than 100 miles since I bought the vehicle, 64k miles currently and just had the full 60k mile check-up according to the dealer) I was coming up a steep hill, and all of a sudden the car started rapidly decelerating, like I was hitting the break. It seemed like it downshifted because you could hear it rev up as it slowed down and the RPM needle shot up by 1,000-1,500.

This problem is now consistent, at all speeds. It will either accelerate way more than is needed with *NO* change on the gas pedal, or decelerate rapidly and seemingly downshift. The car is actually jerky, it is highly noticeable to anybody in the vehicle. I'm taking it to the dealership tomorrow, and have not been able to speak with them about this yet.

Bottom line, what might it be? I don't want to go through half a dozen half-assed repairs because the dealership is trying to save money. I bought a 4-year warranty for $1500 with it that covers absolutely everything and anything that might happen with the vehicle, so I'm covered there. I want it done right. (I'm rather paranoid about car repairs after dumping more money than I should have into a couple of Ford Tauruses over the last 6 years)

Any suggestions would be greatly appreciated.....Hope I didn't buy a lemon

[ray_h71]

The thought occurs to me that just maybe the throttle and/or cruise control cables need lube. But, there could well be more to it than that. The first thing that has to be done is hook a scanner up to the OBD-II port to check for fault codes. Then go from there.

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