How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Tom Your Own Question
Tom, ASE Certified Technician
Category: Car
Satisfied Customers: 25954
Experience:  ASE Certified Master Technician
Type Your Car Question Here...
Tom is online now
A new question is answered every 9 seconds

I have a 2003 Kia Optima 2.4 motor automatic transmission.

Customer Question

I have a 2003 Kia Optima 2.4 motor automatic transmission. I have had the transmission replaced due to a slipping issue with a used transmission with only 5,000 miles on it. Now, the transmission will not upshift on its own. You have to shift to neutral and back to drive and it will go into whatever the speed allows. ONce you are in overdrive and you start to slow down it downshifts perfect. Any ideas would be greatly appreciated.


Submitted: 8 years ago.
Category: Car
Expert:  Tom replied 8 years ago.
Ok the most common problem is faulty shift solenoides on the transmission especially if this was a salvage unit ,when they sit for awhile the tend to short out or malfunction id start by replacing the shift solenoides
Customer: replied 8 years ago.

Unit was out of a driveable wreck, it was removed and sent directly to my mechanic, shifted fine before the install. Downshifts perfect, drive to neutral back to drive creates a shift, if you do this it will shift all the way up to overdrive.

Expert:  Tom replied 8 years ago.
Ok still could be a shift solenoide problem,could be from the impact if it was a frontal collision,if the solenoides are not the problem could just be in the wiring when the new unit was installed possibly pinched wire or connector connected to the wrong solenoide but if there is no check engine light id start with the shift solenoides
Customer: replied 8 years ago.

I have 27 years experience, just not familiar with Kia transmission. No wires pinched and all connections are good. NO codes set, this vehicle has a sport shift mode that also does not work.

Expert:  Tom replied 8 years ago.
Well id still start with the shift solenoides which are common,if not then it could be the transmission you have gotten is bad ,or the computer itself is bad since there was no issue before im leaning towards the solenoides or bad unit
Customer: replied 8 years ago.
any other suggestions?
Customer: replied 8 years ago.
The reply we received were not satisfactory and we asked for someone else's opinion and never heard back from anyone else.