I've a 1990 Ford Fiesta 1.1 with HCS engine and twin choke Weber carb (94K miles). Its got a full service history and is well-maintained.
It ran fine until recently when on a long motorway trip it started to run out of power. The car runs fine at idle and when accelerating up to about half throttle. Pressing the accelerator beyond about the half-way mark, results in the engine sounding like its gasping for breath and it actually accelerates worse. Acceleration up to about half throttle seems normal. On even a slight incline I can only get about 40mph out of it. There's no apparent mecanical problems (e.g. noise, fuel leaks).
I've checked the air filter & plugs and all are OK. The spark is quite stong to each plug. I've checked the "power valve" diaphragm and it seems OK.
What I's like to know before I start dismantling things big-style is - has anyone experienced this before and is there an obvious solution (e.g swap the ignition module)?
Grateful for any advice & thanks in advance, Bob