I took my car (2006 Honda Civic) to firestone to get an oil change and they told me I should get the fuel injectors cleaned. I was in an Advanced Discount Auto Parts store the other day and I noticed that you can buy a bottle of fuel injector cleaner that you can pour down your gas tank. Is this what firestone would do or would they do something that you can't buy at at store?
The "correct" way to clean fuel injectors is to take them out and use some specialised equipment that also allows you to check the injector's spray pattern and flow, which I doubt Firestone will have - usually only FI specialists do have that sort of kit.
My guess is that they were trying to sell you some overpriced additive that you can buy at the store and pour into the tank. At a stretch the might have the sort of injector cleaner that you hook into the fuel system and run cleaner through that way. The latter is better, but still doesn't allow them to check if the clean was actually effective because the injectors stay where they are...
Did they actually say why they thought your injectors needed cleaning (apart from their bottom line, obviously)?
If you think they'd benefit from cleaning, I might be tempted to spend $10 on a bottle of Seafoam, Techron or other injector/fuel system cleaner and pour that into the tank. That'll still save you a lot of money compared to what Firestone would be asking to do more or less the same thing.
Also, in a lot of cases when people recommend that you clean the injectors, you're better off at checking/changing the fuel filter if that hasn't been changed recently. That's something that's overlooked often and tends to have more of an impact on fuel flow than deposits on the injectors.
I would advise against using any kind of additive or cleaner. Your best bet is to send it to a professional injector cleaning service.
When my car hit 100K miles, I sent the injectors to this place this place. Was fast and inexpensive though you have to live your car being down for about a week. He even gives you a comparison of how fuel flowed before and after.