I agree... And it is a good service... And cleans injectors and cylinders well. Plus improves performance....
This was the end of the article in a well done test actually on our cars... The parts I refer to are below where they say:
"Even at the first check-up (5,000 miles), borescope footage showed intake valve deposits forming. At each subsequent check-up, we noticed deposit buildup continued in the intake valves and intake ports. There was heavy deposit contribution from PCV gases."
"...our borescope videos showed BG 44K® cleaned up piston top and injector deposits."
"The results are in
Near the end of the test, at about the 55,000-mile point, our pros started noticing more performance issues.
The conclusion from the two-year test was that BG 44K® can help keep performance high (combustion chambers clean, injectors clean), until deposit formation on the ports/intake valves built up enough to affect airflow.
"Until design improvements address the negative contribution made by crankcase vapors (which create intake deposits), Direct Injection (DI) engines will continue to have intake deposit buildup issues. DI simply lacks the necessary and traditional fuel rinsing afforded by indirect injector spray. The high heat environment experienced by the fuel injector tip is also a major contributor to driveability issues," says Dustin."
Solutions that specifically address reducing PCV vapors (engine oil evaporation) would be a welcome advancement by the manufacturers of DI engines. A combination of full synthetic, low volatility engine oil, combined with reasonable drain intervals would be one way to decrease these intake deposits. Dustin continues, "If DI is here to stay, then classical methods of engine 'keep clean' will need to be re-vamped to ensure trouble-free engine durability and performance."
