Yep, pretty sure: 3mm hex drive ("Allen key"). I keep one onboard for my TPS fasteners and a 2.5mm for the idle stop screw.
I have one those folding sets of hex keys, but they are often impossible to get into tight places.
The throttle plates need to be held open 3.2-3.6ยบ to idle. (Or something near that. But won't likely idle with the plates entirely closed in the bores.)