Every once in a while I get coupons and ads in mail for getting fuel injector cleaning done at a local chain kinda of auto shop. Does this have any benefits over buying a bottle of fuel system cleaner?
I do believe they can get them cleaner than fuel injector cleaners can, but i have also heard stories of people running Chemtool b12 directly through the fuel rail/injectors with the fuel supply cut off and it does amazing things.
But i am not familiar with what kind of pressurized pump you would need to run b12 through the injectors.
The Fuel Injector Flush that is performed with the fuel rail valve works pretty well. Ford has a special chemical cleaner that you mix with gas in a container that has to be pressurized with compressed air.
After you first have it done your MPG's will drop so it's a good idea to drive maybe 50-100 miles then either reset the PCM or D/C the battery so your PCM will relearn the fuel adaptives.
It made a pretty nice difference in my car.
There's an engine shop here that cleans them for $25 each. It's a chemical bath with supersonic excitation or something, then they flow test them. I'm sure it works great, but for $200 (V*8) I would be tempted to just spring for new injectors...
If I suspect clogged / dirty injectors, I pull them and send them out to get professionally ultrasonically cleaned / flowed, screen buckets replaced, etc. I have used Cruzin Performance several times and have been very happy with their services, and their prices are well under $25 per injector.