Dreaded footwell multi plug!!!

[flyin2wheeler]

If some of you maybe remember...i had an electrical issue on my hdi 90 saloon,2004 when some times it wouldnt start,then it wouldnt lock,computer running all the time,then it wouldnt switch off,etc,etc
got a tip off to check the multiplug in the drivers footwell and sure enough it was dirty and corroded
cleaned it up as best i could and yeah,everything worked great.also i had water getting inside at the footwell but blocked bulk head drains seem to have been the problem.
a few days later,some problems return,abs light came on and it was related to the multi plug.
I have also noticed i really have to floor the car latley to get it to go.performance seems to be down and my question....is it possible that poor low down performance is related to that multi plug being dirty?
over 3 grand on the revs the cars fine but its dead under 3 grand.
I split the plug tonight,cleaned it with contact cleaner and then dried with compressed air and performance i think is back up again,is this possible or does anyone know what the wires at that multi plug function?
Im thinking one of the multi plug wires is related to the air flow meter in the breather,could i be correct and that this is giving me poor performance low down
thanks