I did experimented with your theory yesterday, & I found same issue with my Lexus as well, but if I am using cruise & dis-engage it, this is not the case, this is only in no cruise mode, I mean I am using manually accelerator, but if i restrict it to 4th or 3rd, makes a reasonable speed, if the car had already achieved the final gear, this will not happen, but if the speed is slow & one gear is still pending to be engaged subject to the wait time so a reason able speed is achieved, I the release the accelerator same thing happen.
I did this experiment on my MK1 as well which is 1997 only had 4 gears, this doesn’t happen in my MK1 & I have only noticed this in MK3, now I am concerned, if this ecu fault or something else, I have check my balancing & tracking both are perfect.
Now tell me, have you checked with both cruise & manual speeding & also achieved final gear & in another instance one gear deliberately left to be engaged what is the response of your car.
Hi - I'll try this. If you've noticed similar, it's probably ok then (I hope).