I have a 2005 Acura TL. The vehicle instruction booklet states that 91 octane is “required” for my engine, but my engine is equipped with a knock sensor.
I asked my dealer a while back if using 87 will “damage” my engine, and their response was that it will not damage the engine, but it will build up carbon deposits faster. I assumed this was because 93 had more detergents than 87. So I decided to stick with 93.
But then I came across this article:
The article demonstrates evidence that Mobil 87 uses as many detergents as Mobil 93. So I drove on 87 for 400 miles (I got the tank as empty as possible before filling it each time). I didn’t experience any audible pinging or knocking, and my gas mileage was unchanged.
I went back to my dealer and presented the above article to them, and asked for a comment. Their response was that 87 would lead to more carbon build up, not because of fewer detergents, but the way that 87 “burns differently in the engine.”
So I recommend adding the following question to your website FAQ, along with an answer: Will 87 lead to more carbon build up, not because of fewer detergents, but the way that 87 “burns differently in the engine”?
For those individuals who respond, please have citations or mechanical/chemical explanations to backup your claims. I’d really like to get to the bottom of this. Thank you.