transmission problems

[wad]

I have a 2001 optima. My transmission gets stuck in second and third gear.
I drive and going down the road it jumps from first to third, fourth to third. When this happens it will not let me have first or fourth.when shifter is in drive it will stay in third,if i use the auto stick I can use second but it is hard to get it in second. When I need third it jumps in to third and rpms go high when it jumps. When I have it in second and I put shifter in drive and then go back to the auto side it is in third.

If you have any suggestions they would be very much appreciated.

[KIAOPTIMAMAN]

im having the same problem as well
i can put in drive but slow start like starting out in 2nd gear
put over in shifter lever it shows 2nd gear when i bump it forward it jumps into 3rd gear and wont let me have 4th gear
at a stop i shift down but wont let me have 1st gear

[01OptimainMO]

Not sure if you have already taken care of this problem but it is good info for those who are having this problem. You might be getting a code P0720/ P0715 or any number of codes like that. The fix is high low speed control sensors on the transmision itself. I took my car to a transmision shop and had them replace those sensors. I have not had any problems since then.

The reason it only uses 2nd and 3rd and mostly just 3rd in Auto mode is because it does not know the speed to move it from gear to gear so it just stays in a "limp" mode so you can still get it to a service station and get it repaired.

[KIAOPTIMAMAN]

hey thanks for the reply
how many of these speed sensor are there?
and maybe a price on them

[sneakycyber]

AWESOME I have been pulling my hair out to find the problem for mine I was set to buy a new transmission for my car. I will post how to replace them and where to find one later on.

[sneakycyber]

So far the only sensor I can find is the Vehicle speed sensor. I have gone through the entire Schematic for the transmission.

[sneakycyber]

Confirmed with my scanner and with the Kiatechinfo.com

Code No.P0720 Output shaft speed sensor system
Probable cause

If the output from the output shaft speed sensor is continuously 50% lower than the vehicle speed for 1 second or more while driving in 3rd or 4th gear at a speed of 30 km/h or more, it is judged to be an open circuit or short-circuit in the output shaft speed sensor and diagnostic trouble code No.P0720 is output. If diagnostic trouble code No.P0720 is output four times, the transmission is locked into 3rd gear or 2nd gear as a fail-safemeasure.
Malfunction of the output shaft speed sensor
Malfunction of the transfer drive gear or driven gear
Malfunction of connector
Malfunction of the TCM

Test the input shaft speed sensor located below the torque converter.

This of course requires removal of the transmission.