MAF readings with Trans + and extender

[1987ttype]

I haven't run the direct scan for awhile but last night i made some runs with the DS and i noticed my MAF readings at WOT jump all over the place (and with them my injector PW #'s). I was wondering if this is a normal with the trans +, or should i be expecting a smooth MAF reading. the MAF readings for non-WOT are smooth and steady. I am running the trans + into the cabin so i was wondering if i was getting some inteferance from the spark plug wires and maybe just need to shield the MAF wires going into the cabin. anyone else experience this? thanks.