Last post on Sep 05, 2007 at 1:13 PM
You are in the Toyota Highlander
What is this discussion about?
Toyota Highlander, SUV
#4 of 5 Re: HL Mileage and Octane Rating [nomorebenz]
Aug 12, 2007 (9:37 am)
"computer controlled ignition timing..." is no longer the primary resource for tuning the engien for differing octane ratings, not since the days of carburation anyway.
EFI, Electronic Fuel Injection, is now the primary "adjusting, adjustable" resource for the computer to use to prevent engine knock.
#5 of 5 no....
Sep 05, 2007 (1:13 pm)
timing is modified using the knock sensors to adjust the timing of the SPARK to accomodate lower octane fuels.
EFI just regulates the AMOUNT (and in some cases the timing of) the FUEL; the Electronic ignition controls the amount and timing of the SPARK, which is how knock/low octane fuel is addressed.
EFI won't address low octane fuel.