Jackd,
What do you mean "air intake system" if you are referring to the possibility that the air filter is clogged, the filter is brand new, but I haven't even been able to run with it, as I'd spend too much time removing it to make adjustments. The air sensor plate and all other components have been checked. no leaks nothing binding, no vacuum leaks (now that I found the one MBDOC referred to) all potentiometers read correct as per my 'Mitchel on demand' manual.
It feels as though when I accelerate the central plunger opens up the slits in the feed lines of the fuel distribution unit too much and nothing in the system is able to overcome it. So huge amounts of raw fuel get sucked into the cylinders and the spark is unable to cope and eventually the motor stops running. Screw in new clean plugs and I can get it home.
There has to be something obvious that I'm missing.
Michael