My Sonata is a 2002 V6 LX with 131,000 miles. When driving the car the automatic transmission's RPM's will sometimes rev and come back down. When driving in the automatic sport mode the transmission operates perfectly. I first thought it was a transmission problem, but I am wandering if anyone else has had a similar problem.

 

Has the transmission ever been serviced in that 131,000 miles?

 

service trans complete fluid change at 75,000 miles and at 130,000 miles

 

Fluid, reset adaptive, and make sure TCM and PCM is all up to date.. few trans programs running around.

Have to plug it into GDS and do ECU Upgrade search.