Whats a good/effective fuel injector cleaner I can get at Wal mart, NAPA or O’Reilly? Does price/brand indicate quality/effectiveness? Is it more effective to add two bottles (double the dosage) with one fill up?
Techron.
Is it more effective to add two bottles (double the dosage) with one fill up?
No, instead use them in a couple of fill ups.

I used Toyota fuel injection cleaner on my Lexus IS220D (diesel) before the MOT (Pollution) test here in the UK. Have been doing motorway driving. Put a litre in at 1/4 tank. Got a rating of 0.02 with the max allowable being 0.3 absorbtion coefficient.
That's running normal diesel from Shell. 17 year old car, 3 keepers. I know diesel isn't popular in America and these engines even less in the Lexus community, but I'm getting 51mpg and I haven't got around to changing the fuel filter or cleaning the injectors in the year since owning it.
