There are two fuel rails and all three injectors have to come out when one in the rail is changed. They can check to make sure the injector is electronically functioning with a resistance test, without having to remove the fuel rail. Depending on the position of the injector they may be able to get at it without removing much. If the resistance is correct it still could be plugged. Trying a $2.00 bottle of injector cleaner from a Auto parts store and driving at highway speed for a while may also help. If a injector is clogged it just might need a little help to clear itself.
When dealing with shops especially dealers it is best to tell them "my car chugs". If you tell them to change the injector and they do and the car still has problems they only did what you told them. I do not like paying what I think is outragous labor fees at many shops.
It took me 3 hours to change mine myself. The first time I ever tried something like that. I tried to get by with a old seal that looked fine and it leaked. The second time I had to do it to changed that seal. It took me less than a hour. A seasoned toyota mechanic should be able to do this in no time, however somethimes we are at their mercy. If you email me directly I could return email you my phone # if you would like to talk on the phone. DJ
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