Right i have an idea for ya.....
I assume ur looking at the plug located up at the throttle housing, this plug has wires cut, mine too. i discovered that it was probably for the air mass meter newly located just after the air filter. the wires have been cut and a new loom added down near the air filter with an aftermarket mass meter.
I think ul find the throttle position sensor still located just behind the plug underneith the throttle housing with wires still attached.....
I had the problem with the rising and lowering revs, on mine this was caused by a build up of crap on the butterfly valve. just take off the ally pope to the throttle body and clean the valve and u should be running like new again........
