My 1989 8 valve gti has today developed a problem. The performance is very 'lumpy' with an associated loss of power when above 2500rpm. I also have a Corsa which had a similar problem above 4000rpm and it was the airflow meter at fault. Could it also be the knock sensor or a fuel supply problem? All help appreciated. I have a spare ECU and TCI switch which I changed on my car with no improvement, the plugs and distributor cap are fine. The symptoms suddenly appeared on my way home from work today.
