Stratman
MB Enthusiast
The surge could indeed be caused by the gearbox, if indirectly.
If the 'box hangs on to second gear too long as you slow the revs will drop too low, and the ECU could well engage some sort of 'anti stall' mode by automatically increasing the fuel flow into the engine. The puff of smoke you see would tend to back this up.
If the 'box hangs on to second gear too long as you slow the revs will drop too low, and the ECU could well engage some sort of 'anti stall' mode by automatically increasing the fuel flow into the engine. The puff of smoke you see would tend to back this up.
