Hello, I'm having an issue with my 2006 Mazda 6. It has the 3.0 Ford Duratech V6, with a six speed Aisin automatic trans. Lets say I'm going 55 mph in 6th gear, and I give it a little gas to downshift to 5th, the whole car shakes and it has trouble accelerating and shifting. It only does this on really gentle accelerations. It will do this in any gear where I'm cruising at a certain speed, and I want to give it some gas, it just shakes the car and won't make the shift down a gear. I've been having to use the manual tiptronic feature sometimes because it won't correct itself. If I put the pedal to the floor, it accelerates pretty normal.
My car has 179000 miles.
My car has an automatic transmission.
What you are describing sounds like possibly low transmission fluid, a bad speed sensor or potentially a faulty transmission control module, which also controls the speed sensors. The transmission control module has various sensors such as vehicle speed sensors, wheel speed sensors, throttle position sensors, turbine speed sensor, and transmission fluid temperature sensors that all direct information to it in order for it to perform it’s function. Other functions controlled by the TCM are components such as a kick down switch, traction control system, and cruise control module. Any of these may also affect the way the transmission control module performs and controls the transmission and the shifting of your vehicle. A faulty transmission control module may cause also cause a delay in acceleration or erratic shifting of gears. I would suggest having a professional from Your Mechanic come to your location to properly diagnose your transmission problem.