Code P0734?

TANK1995

MEMBER
2005 KIA SPECTRA
2.0L
4 CYL
2WD
AUTOMATIC
2,030,567 MILES

Hello. I'm having a 4th gear incorrect ratio. The other code is p0700. I have jerky shifts, no pickup, high rpms. Would the speedometer sensor cause this? Aside from that, what else? All shift solenoids were replaced. Before they were replaced, there was delayed shifts into 4th (a tap on the accelerator would make it shift) and a code for the torque converter

Monday, May 5th, 2025 AT 5:36 PM

1 Reply

KEN L

MASTER CERTIFIED MECHANIC
51,603 POSTS

Can I ask if the speedometer is working normally? If not I would replace the output shaft speed sensor, if it is working I would replace the input shaft speed sensor.

P0734 - Gear 4 Incorrect Ratio
P0700 - Transmission Control System (MIL Request)

Also, you might want to try servicing the transmission because worn out or burnt fluid can cause this problem, please go over this guide to help you step by step.

https://www.2carpros.com/articles/how-to-service-an-automatic-transmission

Here is the fluid you should use.

A/T Fluid Type .................... GENUINE DIAMOND, ATF SP-III or SK ATF SP-III

For the input shaft sensor you will need to remove the shaft cable and bracket. Check out the images (below). Please let us know what happens.

Images (Click to make bigger)