We have a fairly steep onramp near my place of work, and given the traffic and the lay of the road, I try to make sure I'm doing 70 by the time I hit the end of the ramp. Sometimes it's not possible because I'm behind a semi, and that means getting out of the far righthand lane and into the middle lane at a good clip. I keep it in third, hit WOT, and lane change to get merged into the rest of the traffic. This puts me comfortably at 70mph or so, and I shift directly into 5th and apply the appropriate amount of "cruising throttle". I've noticed that immediate after this shift, the engine sounds VERY rough for a few seconds, and then the sound is gone. I've noticed no strange vibrations through the gearshift, steering wheel, or clutch. Only sound. I've only heard it twice, though, and both times it was strange enough that it made my spidey-senses tingle that something was potentially Very Wrong.

Am I hearing the butterfly on the "active exhaust" closing?
Thanks for any ideas you guys might have.

 

what does WOT mean?

If you're pushing the engine hard and then heading straight for 5th, i wonder if that has something to do with the vvt-i system...

 

Wide Open Throttle.

 

thanks

 

That sounds to me to be a valvetrain issue of some sort, either in timing or valves not opening/closing in the proper sequence.

 

maybe try putting it in 4th then right to 5th instead of skipping 4th

 

warranty is always an option...but who wants to bring it to the dealer so they can say "we couldn't replicate the problem" argh!

 

Just listen and keep an eye on your drivetrain. If you see any leaks or have issue start to show up TAKE IT IN. I also wouldn't tell them about anything out of the ordinary that you did "like shifting from 3rd to 5th. If you dont notice anything like I mentioned above dont worry about it and use ALL of your gears.