Quote:
Originally Posted by Serybmw
Greets from Moscow!
Could you please help me to resolve the issue with the exhaust flap in the left pipe? As far as i understand while installing M Performance exhaust you should remove the flap valve from the standard exhaust and install it into the Performance one, right?
What if not to install it back and instead leave a cover which presumably comes with Performance exhaust, on its place? Will there a be an error sign?
And one more thing. The dealer does not recommend to remove the flap as "it influences the gasoline fillability of the cylinders on low revs and therefore the power will be decreased if the flap is removed". Does it sound reasonable? What do you think?
Thanks!
|
No the M performance exhaust will come with a new flap and the actuator, so you do not have to reinstall it. It will come with everything your old exhaust had.
If you choose to leave the flap fully open, your best option is to remove the spring between the valve and the actuator and tie it off with wire or use a clamp.
From what I have heard if you simply unplug the valve it won't throw a check engine light, but it will throw a code that the dealer will see.
If you just take the spring out and tie the butterfly valve the actuator still works when plugged in, so there is no change to the behavior of the car. Not sure how why your dealer thinks this affects fuel. There may be something we don't know but all I know is my car is fine after 8,000 miles without that spring in it.
Honestly I believe that that valve is there for droning purposes as the drone and exhaust note does go up if you take the spring out, especially at very low rpms. Once you go full throttle even if that valve is closed without the mod it instantly goes open.
One thing to remember, anytime you put on a higher flowing exhaust on your car, you will always lose a bit on the low end, but gain a ton of power up top. Naturally because your car is flowing much much better.
I've been around performance cars a long time and an internal combustion engine is an internal combustion engine no matter make or model.