I was just wondering if I could use 87 in my car sometimes. I was told that I could only use 91 or higher or my engine would blow. I've never owned an Audi before so this is new to me. I didn't get a manual with my car either so I can't just look it up and see. I use 91 now but with 87 being cheaper and sometimes being low on cash I was wondering if it would hurt to use 87 once in awhile.

 

You will not blow your engine. The car will pull timing and you'll lose power. Over time you may develop some issues or throw a CEL, hard to say. But being real, at 20c per gallon difference, you would save $1.60 if filling up from dead empty using 87 vs 91. If that $1.60 is that crucial, you really shouldn't own these cars. I'm not being a jerk here, I'm telling you like it is - in a car that could suddenly require $400 in parts and 5 hours labor on a whim, trying to drive one on a really REALLY tight budget isn't wise. In that case, sell it for a Honda, which runs fine on 87, gets far better mpg, and breaks far less often.