are you unplugging the TPS or the idle switch? The TPS is a three pin plug with a push clip to release. This is used on automatics only and is for the transmission to know where the throttle is for shift points. I believe it also helps with fuel mixture, but unsure on this. Both Auto's and Manual's have the idle switch. It's a three pin connector that's held on by a metal clip. This needs to be set properly for the vehicle to function to it's fullest ability.
Hook a multimeter set to continuity to the lower two pins. adjust until you're just a cunt hair from continuity, when you tighten the bolts (don't put too much torque on these, they are extremely weak!) it should drag the switch forward enough to be spot on.