My '89 Ford Temp with automatic transmission worked fine this morning. Took it for short trip tonight and all of a sudden it would not shift for a long time at a speed of about 29 MPH in low and then it would stay in second a long time and would finally go into third. Down shifting I could really feel it go into low. This came about all of a sudden. Is there a vacuum line that I should look for that may have come off? I did a quick check of the tranny fluid and it looked fine. I will give a closer check tomorrow but certainly there are no leaks where it is parked. Any ideas??