UK Car Repair: Fiat punto 97 75 sx, fiat punto, fiats

Question
Not sure if fiats are your area, but I have a intermittent misfire or loss of power. Ok at start up, misses when warm. So i checked the usual suspects. The engine dipped when each spark plug was removed (all 4 cylinders), but when checking the injector plugs, i isolated one that when removed made no difference to the engine. I assumed that it was a faulty connection (when reconnected it solved the problem for about a week) but when i checked it the next week it was a different injector plug that was the problem. I cant understand why removing a spark plug made the engine dip but made no change when a injector was disconnected. still have the problem today.

Answer
Well you have used common sense so far.  The problem is most likely in the connectors, moving them seemed to solve the problem temporarily.  On the cylinder that is misfiring, try switching the connector from the closest injector and see if the problem stays or changes to the other cylinder, this will tell if in fact it is an injector problem.