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I have a 1983 Jaguar XJ6 Series III with Bosch fuel injection and ignition control system.
My current problem is that at certain RPM, around 2000 rpm, the engine will cut out and in again. I have tried to simulate it in the garage and I can make it hunt around this speed. The plugs look a bit sooty but I only do short trips struggling to reach 5000 Kms in a year. In recent years I have had various components replaced; ignition amplifier, distributor, coil, torque converter, and have had the air-flow meter cleaned. This is now the suggested culprit but how can I tell other than by trying a replacement at great expense. I would not mind this cost if I could be sure it would fix the problem.
Has anyone out there had a similar problem, and found the fix for it?

Regards, Arnold Goldman
Blairgowrie, Australia