more info: the dribbling effect (I really don't know what to call it) happens when the car is running at about 60-65 kph most of the time but sometimes it occurs at 40-50 and above 70kph! The same effect when you run it on paved nor asphalt roads. What I do is slow down the car and wait for it (dribbling) to stop then accelerate until it happens again, btw my car is an old 87' mitsubishi (box type) lancer