Ignition oscillations ? at speeding up

Hello, with my 93 TID 125 HP BJ2001 (120tkm) I have the following problem. When “gassing” (in every gear) I have irregular “slips” (driving backwards), sometimes several consecutively, then again for 2- 3 accelerations no “sorry” (sorry). BAB-driving with cruise control (approx. 130 km/h) feels as if strong Böiger headwind prevails. No warning lights, no entries in the error memory. The workshop has read out the “SOLL list (?) and compared, no differences. tell the workshop, suspicion that a sensor is saying goodbye, or an injection nozzle is dirty. Continue until the error ” becomes more obvious”. has one of you an idea. (sorry, have done me hard at the error description) You all good drive hpv