Originally Posted by
Rico
So at 70mph you feel it slip into overdrive every once in a while? The PCM should command the TCC at about 55mph or so.
If your RPM is around 1900-2100 at 60 mph then you should be in overdrive.
If RPM is 2300-2500 at 60mph then you are stuck in 4th gear.
Since there's no DTC then I would assume that the computer isn't commanding the TCC.
This may be due to a vacuum leak or a bad MAP sensor. Vacuum and MAP sensor are integral to PCM for tranmission control.
I hope the problem is a vacuum leak or a bad MAP and not the valve body in the transmission.
