I have an Independent shop recommend a cleaning service much like other shops to control carbon buildup,,what do you think?

On the second and third generation cars I think it's definitely advisable.

Fuel cleaning service? If it's for an S or JCW (or any direct-injected car), it's a waste of time and money. The carbon buildup happens in an area that never sees any fuel at all, so cleaning up the fuel parts won't help that.

So it was done for $99 by Indy shop
Maybe a good idea, was advised by another mini shop too
But I've also heard walnut blasting needed done later

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Running ANYTHING through the fuel system on a DI motor will do nothing clean the valves...
Unless you have a good reason...like a sticky Injector, etc, it was just an upsell....otherwise known as a way to increase a customer average ticket....it is likely the guy selling the service got a bonus for selling it, and the product used was about $15.....just slightly better than what you put into your tank from Walmart.

And the base is NOT DI...so walnut blaster should not be needed...n12 or n16 are conventional injection, aka port injection.

The cleaner does very little to none on the DI ( S / JCW ) engines the carbon blasting is the best way. https://www.northamericanmotoring.co...-cleaning.html

+1 on the 2007+ Gen 2 NON S can use the injector cleaner.

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It won't hurt to pour a bottle of Chevron Techron in the tank at each oil change. It's a good fuel system cleaner that will help the injectors stay clean & may help the piston tops. But it ain't gonna touch those intake valves.

The fuel system service that shops sell is nothing more than a cash cow for them.