Unwanted accelerating when automatic is in gear/drive. Why?

2000 MAZDA 626
260,000 MILES
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MAZDAHOMER
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  • 1 POST
Got a 2000 Mazda 626 AT Touring, 4 cyl.
When my car is still cold(it happens more frequently when cold), and the transmission is in gear/drive ( its an AT ), and i let my fot of the gaspedal the car sometimes want to do a quick accelerate or jump forward. Its like kangaroo fuel. The rpm goes up and down. But if i quickly brake softly or put shift in neutral the rough rpm sattles and the car runs normal again. I did let my mazdadealer do a diagnostic check but they found nothing suspcious. Can it be the transmission? When i use the "hold" function, from start or at very low speed and doing a kick down, the car feels like it always starts on the second gear. I have cleaned the MAF, changed air filter, sparksplugs etc etc.
// Thx
Jul 2, 2012 at 5:49 PM
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KHLOW2008
  • ASE Certified Mechanic
  • 41,814 POSTS
  • ASE Certified Mechanic
Check the cold start and IAC. Have them cleaned and the throttle body as well.
Check for vacuum leaks.
Jul 2, 2012 at 7:44 PM
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