Hello,

I would, if I were you, make the effort to insert a fuel pressure guage
on the inlet side in the fuel rail. I would then observe the pressure
as you crack open the throttle.

When you say that your plugs fouled, just what kind of fouling did you
see on the tips of the plugs? Oily, carbon, white/yellow? Does any
smoke come out the back of the car? What color is it?

92 Jags dont have a Karman Vortex air meter (Vane) to the best of my
knowledge, they should have the hot wire type know as "MAF".

Locate the ECU temperature sensor next to the thermostat and clean the
connector, better yet unplug it and start the car. These ECU temp
sensors fail and lose calibration and should be included as part of a
30-60k tune up item.

Of course this does not rule out any ignition issues but it gives you a
basis to start.

Best Regards,
Blake