Hello Readers - can anyone help diagnose this fault:?

I have a 1600 cc petrol Dynamic, which has the Engine Fault light and is
either misfiring or running rich - the engine is not running evenly; it's
best described a 'thumping' and no 'pull' on putting my foot on the gas
pedal.
Also, I can hear the sparks being 'lost' as interference on the radio.  I've
taken off the attractive cover for the engine to look for the plugs and all
I can find are the HUGE condensers that feed the plugs - no traditional HT
leads of the kind I'm used to.

Have any other readers suffered this problem and what was the cure please?

38000 miles, petrol OK - not contaminated fuel.

TIA