Mild "trailer-hitching" sensation in Drive 6

[dave245]

I have noticed a mild "trailer-hitching" sensation while cruising in 6th gear at about 80 km/h (50 mph). The effect goes away if you switch to manual mode (still in 6th gear) - torque converter appears to unlock and RPM increases by about 250 rpm.

Has anyone else noticed this? You have to be on a smooth, flat road to notice it.

I have a GT AWD...

Dave

[dave245]

I found a GM TSB that describes a similar condition as "Chuggle" or "Fishbite" on light-load cruise at highway speeds. The issue was related to a defective Throttle Position Sensor (TPS). When tested separately, if it exhibited a sharp voltage drop within its normal range of motion (ie. not a smooth voltage variation with throttle angle), it could cause symptoms that feel like they are related to transmission torque converter lockup. The GM Tech2 diagnostic tool would not normally identify such transient, short duration events so specific sensor testing was required. The ECM would not set any TPS codes either.

I'll mention this to my dealer when I go in for my first oil change in September.

My current work-around is to shift to manual mode in 6th gear at 80 km/h (50 mph). This unlocks the torque converter and the symptoms are dramatically reduced. It feels like engine misfire but the MIL does not flash.

Dave

[DashingMax]

Well, I'm glad I didn't get the tow package.
Hopefully Mazda can quickly resolve this issue.