[boxhead]

Pulling leads and seeing if it runs no worse will tell you whick cylinder is not making power, then pull the plug out for that cylinder - look at the plug end (the end that goes in the head) and see if it is black and shiney (wet)
If it is then you have no spark at that cylinder - No spark can be caused by.
(1) dead plug
(2) dead lead
(3) failed distributor cap (faulty pickup for rotor button)

If the plug is clean and white then there is no fuel getting into the chamber.
To test this you will need to first buy a "Noid light" remove the connector from the injector on the faulty cylinder and plug the lead into the light, start the car and watch the light - if it blinks quickly then the ecu is sending the signal to the injector to make it fire.
I doubt that it is a fuel pressure issue if the fault is only in 1 cylinder.
So if you have clean plugs and a flashing noid light then it may be a clogged injector.

Hope this Helps Pete