I scanned a Felicia 1.3 MPI yesterday and found TPS, Lambda sensor, and Engine Speed sensor faults. Whne I cleared the faults, took a test drive the car started fine, sounded Ok, but had bad flat spots when accelerating and driving around. I scanned again and found only the Lambda Sensor fault with VAG COM.

Would the sensor cause these flat spots?

The EDU was repalced in the car one year ago as the existing unit was "fried" by a fault Alternator Regulator.

Should I be looking at other electrinic parts such as Fuel Pump, Ignition pack etc. as possible sources of this fault?

If you have access to a co emissions machine you could hook it up and check your co at idle and at a constant 2500-3000 rpm (ala MOT) the co should rise for a short period when you accelerate then settle down to almost 0 co, 0.05 is about average with a good lambda sensor and cat at constant 25-3000rpm If it fluctuates it could be the lambda not switching correctly or slowley. If it doesn't the fault lies elswhere and the code for the lambda sensor is the result of poor mixture rather than the fault:(