Perfect!! McLaren doesn't want you to suffer from predictable burbles syndrome something the 991.1 and 991.2 suffered from seriously. Thus the unpredictable sound occurrence rate.

 

LOL. Once they start they do not stop the entire drive, but, turn the car off and back on... they disappear. It's confused me thus far and trying to figure out if its something to bring up with my dealer. I prefer to have them enabled... it sounds so much better crusing around and then when you want to hear the crackle crusing away after leaving somewhere and they are never on for me right after starting the car.

 

My 765LT Spider does the exact same thing. I just assumed it is programmed to start at a certain point as some kind of engine safety feature or something, but I don’t know. I sure would like to know though and I wish they were just there all the time.

 

I've been dealing with it because I knew they'd come on after a few min and rarely maybe 10 min but this last drive wasn't even a full cold start I had been driving some throughout the day and they didn't come on at all in a 15-20 minute drive so now I want to figure it out the reason.

 

I've noticed exactly the same thing but haven't been able to pin it down to a specific time or engine temp.

I believe the delay is to allow the catalytic converters to warm and minimize the risk of damage. The burbles/pops themselves are caused by the ECU sending a temporarily rich fuel mixture through the exhaust. A rich mixture is inherently hard on the cats so, my guess is, they delay this until the cats are at least "properly" warmed. Hopefully someone smarter than me on the subject can opine.

 

I feel that this is the reason. After shut down temps drop below where the ECU allows that rich mixture eliciting the pops...once temps are reestablished, plus a few minutes of drive time they should return. Mine always do.