JonWsTT

I have a 01' 180FWD Coupe. I recently swithced to using 89 Octane (at 4000 miles) as the 93 in the area I was in was just too expensive. Car seemed to run fine, very peppy, no pinging noises or anything. As long as it seems okay, what other "hidden" harm might I be doing to the car? I assume the ECU will adapt to the lower octane and adjust the timing accordingly. Thanks for the help.

Jon W.

HipsTTR

Turbochargers have "ping" sensors. A "ping" will blow out the turbo. SO they do modify the timing to eliminate the "ping".

But the real question is why are you happy with less power? We buy the car for the great combo of styling and performance!

TTeleven

Why? - worst case scenario 20,000 miles/year at 20mpg at 10c/gall difference is only $100 per year

seaTTym

that should give the few extra $$ to pay for the higher octane gas

Rennen

Don't do that....trade in the TT for a Camry if gas price is your concern.

fredfromny

For the 180. But a less than reputable gas station that sells 86 octane labeled 89 will be.
Midgrade of ~91 may be a good compromise.
Usually a dishonest gas station will sell 89 octane instead of midgrade, still leaving you a margin of safety.

BryanTT

A little harsh?

Rennen

Maybe. I wasn't trying to be harsh, just making a point.

OTOF

you'll make up the gas price differential each week.

TTom TTR

$1.95 a gallon here for 91 octane. Save money somewhere else, do your car a favor. they don't require 91 octane because it's a conspiricy with the gas companies, they require it as to not destroy the engine/fuel system.