Can fuel injectors be cleaned?

My BMW was misfiring recently, so I took it to my local BMW dealer. After diagnosis, they said one of the injectors failed and therefore all the four injectors needed to be changed, along with the spark plugs. The total cost quoted is more than £1300. I was therefore wandering if instead of changing can the injectors be cleaned. If yes, how?
At this point, the bast thing to do is to get a 2nd opinion from an independent BMW specialist who may concur and may be able to fix it for you at minimum cost.
Answered by Honest John on

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