|
Zfr5f or 4?
The dealer i just talked to said both of these plugs (zfr5f & zfr4f) are ngk iridium and that they are the exact same plug other than the stamp.
I am trying to re-gain 10 mpg lost after a tune by a guy unfamilar with the special nature of the VX.
I also have a 97 HX to double check.
|