active exhaust turning itself off

[Cpove]

anyone here ever have there active exhaust turn itself off and on while driving? happens under certain throttle conditions.

Sponsored

 

[key01]

Yes. Goes on at WOT. Then off

 

[Cpove]

Mine does the opposite sometimes...I’ll be in sport mode with the exhaust open and it will close it self under hard throttle

 

[Hack]

Only at really cold temperatures, like -10 F or below. Sometimes the valve sticks (I believe), when it's very cold. Usually there's an associated error message which clears itself once ambient temperature is closer to zero or slightly above zero.

Edit: after thinking about it I think I have had what you are describing happen. I think it's due to poor gas causing the computer to pull timing, but that's just a WAG.

 

[Cpove]

im not sure if its sticking because the valves were already open? it goes from being open to closing on its own. Cars a fair weather car and have had this happen in +25C weather

 

[Hack]

im not sure if its sticking because the valves were already open? it goes from being open to closing on its own. Cars a fair weather car and have had this happen in +25C weather

I'm not sure why it occurs, but I think I've had what you describe happen. I think it has happened to me the most on a hot day with the AC on. That's why I was speculating that it was the ECU pulling engine ignition timing due to poor gas/detonation.

If it's the same thing you are talking about, it comes and goes and most of the time it doesn't happen, but every once in a while I've noticed it.

 

[Cpove]

I'm not sure why it occurs, but I think I've had what you describe happen. I think it has happened to me the most on a hot day with the AC on. That's why I was speculating that it was the ECU pulling engine ignition timing due to poor gas/detonation.

If it's the same thing you are talking about, it comes and goes and most of the time it doesn't happen, but every once in a while I've noticed it.

Weird it would be pulling timing but sounds like it could be possible...car only ever sees 94 octane though... you ever have the throttle bog on you at the same time? I’ll be under load and the car bogs out as well

 

[tdzee]

I thought it operated based on throttle position alone, and not other engine operating parameters. I thought I read it opens around 50%. (That's too soon for me on the street and I wish I could reset the program for opening later.) FWIW

 

[Demonic]

I'm assuming you're not referring to 6th gear, right? Because then it will close even if in sport mode.

 

[Hack]

Weird it would be pulling timing but sounds like it could be possible...car only ever sees 94 octane though... you ever have the throttle bog on you at the same time? I’ll be under load and the car bogs out as well

Not exactly bogging, but I do feel as though there's less power when it happens. Almost like the ECU is partially feathering/closing the throttle.

Sequence of events:
-I nail the throttle and initially it sounds normal (the exhaust is loud due to being in sport mode)
-Throttle still to the floor, exhaust gets quieter, subtle reduction in power
-Throttle still to the floor - exhaust gets loud again and the car takes off

Something like that. And usually it seems to be at lower RPM and then it cleans up as the engine starts to rev out, which is a symptom I would associate with the engine's tendency to be more likely to detonate at lower/mid range. I've never noticed it on track, just on the street when I would typically be at lower RPM anyway. It will do something like that if you have the car in weather/wet mode and the exhaust in sport. When it cuts the throttle due to lack of traction you hear the exhaust quiet down. Now that I say that, maybe it's traction control doing it and it's not related to detonation at all.

 

[JJ]

I

I'm assuming you're not referring to 6th gear, right? Because then it will close even if in sport mode.

It actually opens up in 6th when going around 100mph,

 

[nastang87xx]

I

It actually opens up in 6th when going around 100mph,

Not quite. Regardless of drive mode and gear, the valves will fly open at 50% throttle.

Sponsored