Just ordered my Prius, and don't know if it has a specific grade gas it needs, but wondering if anyone has tested to see if the grade of the gas changes the MPG you recieve.
A safe way to go for a more "premium" gas (if you want to call it that) is to get "Top Tier" gas. The standard was developed/supported by GM, BMW, Toyota, and I think maybe Honda to confront decling levels of detergents and additives in gas. Website I think is toptiergas.com and companies meeting standard I can remember are Shell, Chevron Texaco, Conoco Phillps, Quik Trip... I might be missing some. All grades of gas at all locations must meet the standard to be certified. I've meant to search this forum about otbers who've used/researched but haven't. This isn't to say that other gas companies are inferior, only that the comanies meeting this standard have been certified by these car manufactures to meet what they see as good for their cars. Personally, I am buying it since it costs the same as any other major brand and I don't know any other certification place. Only Shell and Phillips in my area, thou (Chicago) kinda sucks, but since I only fill up about once a month I think I can handle it.
<div class='quotetop'>QUOTE(feethanddooth\";p=\"81228)</div> All modern cars monitor their emissions control systems. It's required. When something compromises their ability to maintain low emissions, it throws an error. Usually a Check Engine Light. The dealer can use a SCAN tool to pull the exact code. In other words, premium gas can cause the Prius Emissions Control system to fail.
