At my 97 RAV4 i can access the coils without removing the throttle body.
Moving the (top of the) air box might give you some more room, but not really needed. Unplug the spark plug wires to test them electrically, and check for 'lightning strike' marks there, which indicate very high resistance/ broken wiring.
If it's not broken or indicating high resistance, check if you have Bosch wiring. Those should be replaced even if not giving obvious problems. Many have experienced lots of issues with this brand plug wiring.