Bought 2001 tiburon was driving it home went about 45kms & it stopped shifting in to overdrive so i stopped the car & shut it off & it seemed to reset until you accelerate & it kicks down & then it won't shift into overdrive again

change the auto transmission fluid and filter and check the linkages
perhaps one it loose and not engaging

Hi, Try changing the oil in the transmission and filter. Good luck.

Valve body or torque converter is going bad. Also Some cars have a overdrive off button, make sure you did not hit it on accident

it sounds like transmission trouble take it to a shop cause i dont think you wil have the tools to fix the trans at home

When was the last time you had the transmission filter and fluid changed? Sounds like the filter is clogged.

pressure sensor or shift soleniod

Hello you have a internal transmission problem you will need to have your car hoisted up and transmission further asset a transmission specialist or dealer ship is the best solution this is a big job unless you have allot of previous experience this is my best solution for you.

With key position in off push the shift overdrive button then put in to nuetral then crank the car it will start in N.

why 2000 hyundai tiburon
overdrive sometimes not working

Okay, I baught an 01' tiburon last march. When I first had trouble with the tranny it wouldnt shift into fourth and no it wasnt the overdrive button. Then it started downshiftling like what your experiencing then I lost reverse. Ammco rebuilt the tranny. I would take it to them, they will inspect it for free. You may just need a tran fluid flush. You should know that in the automatics the tranny is the weakest part of the car. The engines are great, just everything around them seems to fall apart after 120,000 miles.
Ammco offers a free inspection service. However Just from experience - if you need a new auto tranny it is cheaper to buy one already rebuilt (with warrantee) and pay to have it installed than to rebuild the one you have.
Cheers to hyundai challenge : )