when i first start the car and accelerate..the car over revs and then jearks realy hard into second gear...after it jumps into second gear, it has very slow acceleration. is my transmission messed up or could it be a sensor or computer issue?? please help
car jerks hard into second gear on 2001 Hyundai Sonata
Hyundai has a few technical service bulletins regarding this issue. I would take it to a shop or Dealer that specializes in Hyundai and have them look at the technical service bulletins 07-40-010 and 08-AT-003. There may be others as well, but these should help to address this problem.
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I had something that sounds a little similar many times since about 2004. They had to replace the "speed sensor" three times. about $300 bucks a pop. Transmission would race (v6, auto, 2001) and sometimes the car would go, other times it would just sit there. Then THUNK! and it would move. Sometimes you could be going down the highway and the car would just feel like it dropped a gear or two and would over-rev- or not even go when turning through an intersection, very scary.
you must have a few problems: check if your moter mounts are broken, then check the colour of your fluid( it has to be pink), if and when you drain the fluid no metal shavings should be present. if theyre present, your tranny has internally damage.