fuel injector cleaning

Hello, the mechanic down the road says that the rough idol on my 84 caravelle is due to a fuel injector not functioning properly. funny thing is it seems to only do this when the engine has been running for awhile. I've just recently switched over to BP ultimate fuel this wouldn't have anything to do with it would it?
Is it a big job to service the fuel injectors or is there a way to clean them out another way. Will this affect performance of the engine in any way?
thanks, I don't know anything about engines.....

[Edited on 7-8-2004 by surfvan]

nobody??

wyhns spitfire or injector cleaner but they can only do so much

remove the injectors and have them cleaned adn have the seals replaced. I do this every other year on my cars and I use EIS they are mobile but there should be someone down there. Oh I pay 25 an injector.

Thanks guys,

555bug, what is EIS?

electronic injector services