Transmission Crunch when Flooring Throttle
 

Hey All,

Not sure if this is an actual problem or not, but I've been able to reproduce it pretty easily.

Here are the steps:

1. Be in any gear (preferably 3+)
2. Coast in the gear with no throttle at all.
3. Apply somewhat good pressure to the gas ( you don't have to floor it, but a nice kick to it to up the revs quickly)
4. For about a half second, I hear a crunching sound which then goes away immediately.
5. You can repeat the coasting with no gas and then give it gas to hear the sound again.

Is this normal or should I bring it in to the dealership?

I've notice the sound doesn't happen when I apply throttle gently or normally. It only happens when I want to pick up the revs fast.

Thanks for helping me get this off my conscience!

I'm having the same problem and another owner on the forum has posted the same problem. Right now, I'm just babying it and trying to be smoother on the throttle in the higher gears. I will keep you updated, but plan on taking it into the dealer after break-in. Keep me updated.

I have the same issue … posted the thread wmak is referring to. I've had the car at the dealership several times with no clear explanation. The first time the car was in they felt it was something on the body rattling and the last time they felt it could be "knocking" from using 91 octane instead of 93. I'm not convinced. Please post if you find a solution.

Thanks

It could be knocking / predetonation, which the control unit senses then backs off the timing to stop it. You could add a can of octane booster to one tank to see if it makes any difference.

Could it possibly be the transmission mount?

I'm still on my first tank of gas from the dealer. Will try adding some octane booster for my first refill. Will let you guys know how that goes (should be refilling later this week).

Sounds like tip in knock to me.

My question is, wouldn't the knock come on for all rpms/gear ranges and not just when the accelerator goes from coasting to being depressed during the higher gears?

No, that's the definition of tip-in knock..when load changes rapidly and timing is too much/afr is too lean..as I understand at least. I bet your dealer put 87 in your car. Don't bother with octane booster, just drive it easy and burn off this tank and fill up with some good 91. If it's knock I bet it will go away by your 3rd tank.

Thanks for the clarification, I will try that and keep everyone posted.

Evo4g63, jb86'd, pantdino … thanks for your input … appreciate it

My car has 9000 miles or so, it's not an issue with the wrong gas. I will try the octane booster. The explanation of tip in knock seems to make sense however I'm just wondering why there aren't more folks in california experiencing this . . . or is there something wrong with my car.

Appreciate your thoughts. Thanks !!

There are many people having this issues I feel. Most just don't seem to realize it and or thinks it's normal. If you only have access to 91oct the chances are it'll do it. A custom tune can help this.

We talking manuals or automatics in here?

Manual …