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Old 10-06-2012, 08:26 AM
anE934fun anE934fun is offline
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Originally Posted by Orient330iNYC View Post
it will only clean the injector.

the issue with a direct injection engine, the injector is in the cylinder. gas additives worked on manifold injected cars as the fuel would wash over the intake valves on its way into the cylinder.

with a direct injection engine, the fuel is injected directly into the cylinder, so the fuel (and cleaning additives) never touch the back of the intake valves.
I have been wondering about this for a while. BMW goes to great lengths to encourage the use of high detergent gasoline. As you post, with D.I. engines, there seems to be little benefit to be gained from using high detergent gasoline (no valve cleaning). Once the gas is burned, the exhaust is no different than what is produced using the non- high detergent gas. Am I missing something?

Last edited by anE934fun; 10-06-2012 at 08:29 AM.
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