I've tried it mine. Instant reduction of FE. As the motor has already seen 185k miles of use I didn't figure it would hurt, and maybe would help a tiny bit. Nope. This HPCR (high-pressure, common-rail) motor didn't like it for "help". A PM from another contributor here indicated that it
may be of help on older, low-pressure motors where the fuel pump is of a different design and used fuel as a lubricant.
I'll stick with ordinary fuel additives from hereon . . where
Standyne Lubricity Formula is the choice of injection specialty shops (serving industry).
This product should be the basis of comparison, IMO.
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