2003 jetta 1.8 t with EYP coded auto transmission
When in "D" (drive) ,transmission shifts good 1st,2nd,3rd, when it needs to shift into 4th it down shifts. does anyone have a clue of what might be the problem?
Do you mean when you start climbing through 3rd instead of going to 4th it downshifts back into 2nd? Normally I'd say a sensor but a sensor should be throwing a CEL if it's bad. If your internal clutch is worn out the transmission may be slipping inside and downshifting in an attempt to reengage. Or it could be a bad solenoid or servo not sending the right signal. Or low oil pressure inside the transmission maybe. Try flushing the tranny fluid and changing the filter. Check the pan magnet for little bits of metal, if there's metal in the pan, your tranny is going bad. Other than that, Idk, that's a tough one.
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