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No exhaust “mods lol”

11K views 35 replies 17 participants last post by  indcline 
#1 ·
Vehicle Speedometer Gauge Plant Car

Had to be a rice-guy and try unplugging the exhaust valve in hopes it would stay open for more sound. Which it does. But the car is smarter than that. No CEL, but you get a reduced power message
 
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#7 ·
Huh. In what way would that third pipe (open or closed) cause a turbo to be uncontrolled?

It might violate California’s noise regulations - presumably why there is a valve in the first place.
If someone swapped the entire exhaust system and put a straight pipe. You wouldn’t have a way to connect that wire back unless you tricked it. That’s the safety mechanism.
 
#9 ·
Semi-related question...

Do we know at what RPM the exhaust valve opens? Or is it a throttle position thing??
 
#14 ·
The brochures probably state RPM based positioning because people know what RPM and speeds are. But it makes more sense to me that it’s based on load because essentially all calculations are based on that number.

More load, more air flow, free up exhaust system.
 
#27 ·
Sorry to reply to a thread a few months late but was curious if after you plugged it back in the error message went away on its own?
I was thinking of unplugging mine to see how it sounds but don’t have my code reader with me and don’t want to go to a dealership if I can help it. Lol
 
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#30 ·
I unplugged mine, and it sounds amazing. It ran with no error code for one day, and then popped up with "reduced power, bring to dealer" warning. When I plugged it back in and restarted the car the error went away. It certainly did not feel like a lack of power, and made the same boost as normal, but the warning message is consistent and very annoying.
 
#32 ·
If left unplugged an error message will show up on the dash. If driven normally and left unplugged no error messages show up. But once you do a full pull you will get one. Or so I've heard? It's open 80% of the time anyway. I don't know why it even has a valve. I could see if it stayed shut until 1/2 to full throttle. Or stayed shut in eco and normal. But it's pretty much open all the time. I removed my valve and used a screw to hold it open 2nd day of ownership.
pretty sure the valve is closed most of the time. It is only open at idle-20mph then it closes. It does not open back up until you reach 4500rpm or WOT(Wide open throttle/ full throttle).
 
#34 ·
Oh, I figured it was always closed above 19 unless 4500/WOT, he says open above 17mph when decelerating. Interesting.

I can't believe anyone runs with it open all the time! The drone damn near liquified my brain driving around town with it stuck open.
 
#36 ·
I don't know if it's just me but I love the drone with it unplugged. It isn't terrible but also is nice to plug back in. The Supras have a thing you can plug in to trick the computer into thinking the valve is working. Is the GRCs valve plug similar? I would love to have that option for more noise...
 
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