Since I added octane boost and then started using premium gas, my car is running great again. So insufficient octane was the problem. Crazy.
Since then, several other sources have confirmed that modern cars do this, though almost nobody I know had heard of knock sensors. And today I ran across an article that describes exactly what happened, and even mentions my car specfically.
High-octane gas isn't just for tuners though. Plenty of stock cars depend on the stuff, including a Celica GT-S with its 11.5:1 compression, or a turbocharged WRX or Volkswagen 1.8T.
What more, my car's manual says they recommend 95 octane, which isn't even sold at gas stations. (In California they only go up to 91 these days.) So the question of the day is: if I boost the gas up to 95 octane, will I notice a difference? A couple months ago I'd have said "no way". Today, I'm thinking about trying it.
Even in TX, I think gas stations only go up to 93 octane generally.
ReplyDeleteOh, and my housemate Brian Kidder (did you know him at CMU?) knew about knock sensors. They're apparently basically little microphones in your engine, amusingly enough.
ReplyDeleteActually, I knew about them too! :-P
ReplyDeleteThey were mentioned in the auto mechanics class I took some 5 years ago. Not to say that I'dve had any clue that those were causing your problem, just that when you mentioned them I thought "Oh yeah, I remember those!"
heh, I suppose that auto class was good at least for knowing what my friends are talking about :)
If you’re really curious, you can try filling your tank with 100 octane race gas. Finding this rare delicacy used to require going to racetracks or removing your catalytic converters, but it is possible to find it at a select few Unocal 76 stations. I know the one in Redwood City has it at two of its pumps, I’m sure it’s a more widespread phenomenon than that though the internets have failed to generate a list of them. It’s a little bit pricey at $4.50 per gallon, but this is for science, and regular gas will cost that much soon anyway.
ReplyDeleteMy car’s knock sensor is supposed to adjust its timing for anything between 87 and 100 octane gasoline, (insert inductive step), so your car should handle 100 octane gasoline just fine. As an added bonus, it makes your car smell just like a real racecar!
THE 76 STATION ON 3010 ALMADEN EXPY HAS 100 OCTANE AT 2 OF IT PUMPS TOO
ReplyDeleteREMEMBER ALMADEN EXPY NOT ALMADEN