Big Hank

Being tired of always having to push the sport button every time I start the car, I have removed and plugged the vacuum lines at the tail pipes. Sounds great all the time!
Question is, are there any adverse effects possible due to possibly running much of the time with the sport mode off thus leaving the throttle mapping normal?

ELEVENS

I've been running that way for three months - no worries.

abwc

I would guess that's fine, no worries.

Pete @ Stratmosphere

air/fuel to supply more fuel. No confirmation yet. Just a rumor. -Pete

RI A6

Pete,

That should not happen under normal driving, in order to meet emissions. The ECU closed loop lambda control is very picky about keeping A/F mixture at the optimal ratio for low emissions. But, it is possible during acceleration and WOT that the Sport button increases the mixture enrichment factor. I've had a nagging feeling about that for a while.

Since I run sport mode all the time, and I've been seeing fuel dilution issues with the oil, I wondered if that might be the cause. So, recently I've made some oil tests with sport mode on for 500 miles and off for 500 miles, to see if there are any differences. If there are, I would expect it to show up in the oil.

ELEVENS

I suspect there's an "accelerator pump map" in the ECU, which might have been richened up to increase throttle response in Sport Mode. Carburetors (remember those?) have adjustable accelerator pumps and that function was mimicked in the GM ECU's I used to program (1985-early 1990's).

Maybe emissions and/or fuel consumption isn't as much of an issue with a car that has a "Sport" button that's off by default. Probably need an army of EPA lawyers to get that Q answered

Sorry no hard facts, it's all conjecture at this point. Looking forward to your fuel dilution report. In the mean time, my muffler valves remain open and Sport remains off (with the "golf tee mod").

Pete @ Stratmosphere

The owner of Milltek told me he thought it was so, but no real confirmation.

SprintblueRS4

Re: you messed up your warranty

ELEVENS

No, but warranty shmarranty. Hell, I bored and stroked my brand new Corvette.