Clicking noise during engine loading/unloading
 

I've searched around the forums and found similar posts, but not this particular problem, so maybe you guys can help me out.

So for the past 6 months I've started hearing this "clicking"/"twig snapping" noise every time I load/unload the engine (basically, while in gear, press and let-off the gas). The noise can't be heard from the inside with the windows up, but can be clearly heard from the outside with the windows rolled down. Could hear it quite clearly in enclosed areas, like a parking structure, or if driving right next to a building or a wall. The noise can be heard in 1st, 2nd and reverse, by the time I'm at 3rd and up, I think wind noise is just too loud to hear it, but probably still there. The noise has since gotten more "dull"/not as loud, but still audible.

I've taken it to a couple Subaru dealers nearby: one flat out told me it was normal, the other did say it was odd, did a once over on the rear suspension thinking it could be a CV joint problem, and didn't find anything out of place, and told me to "keep an ear on it!" Ha...ha...:paddle:

Things I've done:
-Recently installed Ohlins coil overs before the clicking started. Went ahead and re-torqued all the mounts. Clicking still there.
-In my forum searches, found a couple of threads mentioning that it could be the axle nuts. First tried to re-torque them, but the clicking persisted. Knowing that the nuts aren't really meant to be reused, I went ahead and replaced the nuts, which didn't get rid of the clicking.
-Put the rear on jack stands, placed it in gear, and tried turning one of the wheels back and forth, basically looking for any backlash in the drive line and checking the axles. Nothing really weird other than some play in the drive shaft, but that was common and produced a different sounding click/clunk (I'm running out of onomatopoeia).
-Put the whole car up on jack stands and just shook/wiggled the sh*t out of everything, trying to find something that's loose. Found nothing.
-Checked and re-torqued my engine, transmission and differential mounts.

Things I've left to try:
-Replace trans and diff fluid (highly unlikely, but worth a shot)
-Pull the trans and check the clutch (not looking forward to that)
-Take off axles and actually inspect them, the CV joint and wheel bearings myself.

I'm running out of ideas, so hopefully you guys can give me other things to check.

Any help would be much appreciated!
-B

Update 10/20/15
Finally got the car back up on stands. Noticed that by rocking the passenger rear wheel while the e-brake was on reproduced the clicking noise I hear on one side. Tried to capture it on video but quality is pretty bad

[ame="https://www.youtube.com/watch?v=C3jyFw0BKHg"]2013 brz rear clicking - YouTube[/ame]

Lots of shit it could be, your description is insanely vague, my money is on the drive by wire throttle, it's pretty loud, watch Dezoris' video in this thread:

http://www.ft86club.com/forums/showthread.php?t=67295

Post a video (or be more descriptive), I could speculate anything from axle nuts to DI seal failure, all you've said is 'twig snapping noise on or off throttle'.

There in lies the problem, you can see I'm scratching my head aswell, looking all over the place and trying everything I could think of. Sorry about my vague description, but I wasn't trying to be vague due to laziness, it's just that I have no idea where it could be coming from other than its audible from outside the car.

I've tried taking video with an external mic located in the places I suspected, but didn't have any luck capturing it. Even tried filming at a mostly empty parking structure, but again, all you can hear is a click from "somewhere".

Thanks for the throttle body suggestion though, I can stick my external gopro mic on there to see if that is where its coming from.

Well, I'd suggest you start there.

Start by doing what ...... ?? Heck, I don't know ...... they didn't have coil overs, on regular cars, back in my wrenching days ..... :(


humfrz

Checked the throttle on my way home. Definitely more related to the drive line than the throttle since I don't really hear it if the car is in neutral.
That was my first suspicion, which was why I went through all the coilovers bolts and retorqued them. I suppose I can swap back to stock and see if it solves it.

I had something VERY similar to you. The sharp click noise would only happen when I would engage or disengage the throttle. Easily could hear it if reversing backwards uphill.

It was the axle nuts 100% if you had them replaced already I would have them 'overtorqued' because the nut itself needs to have a slight divet I believe to be fully latched in. I've had this clicking issue on both the passenger and driver side axles. Replacing the nuts and torquing slightly past spec fixed the issues permanently. Subaru drivetrains are notorious for axle/axle nut issues. Found my fix over at the Nasioc

Let me know if that works 😉

Ya, I actually found your post about it, which was why I replaced them, although I just torqued them to spec instead on going higher as you mentioned. I already put the divet on though, so can torque it more unless I replace them again.

it's probably the cheapest thing to try atm to fix that issue. I would order two new axle nuts (I think they are 7 or 8 bucks) and slightly over torque them.
I had a shop replace the axle nut and I still heard it clicking a day later; took it to an actual performance shop, they overspec'd it slightly and it was fixed

A click? Mine does it sometimes & im positive it's from clutch or the release bearing. (I'm just guessing...xD but probably not where your noise is from)

So did a few things over the weekend:
-Stuck my gopro mic in the engine compartment. Verified that the clicking was not coming from the throttle.
-With the car up on stands, cycled the ohlins with a jack to simulate the car lunging, no clicking heard.

-Replaced axle nut and torqued to 10 lb-ft higher than spec, still clicking. I'll probably call it quits on the axle nuts since I don't want to damage anything/not be able to take them off (Already had to use a pipe to extend my breaker bar to take off the driver's side).

I've been suspecting this for a while but could not get myself to pull the transmission to check. Any tips on what I can look at around the area? I can probably try to stick my go pro mic down there for kicks...

Quick update, was able to reproduce the noise. Car was on jack stands and e-brake engaged. Clicking was reproduced by rotating/rocking the passenger rear wheel back and forth. @The Racers Line so these are probably axles?

[ame="https://www.youtube.com/watch?v=C3jyFw0BKHg"]2013 brz rear clicking - YouTube[/ame]

Do you have time to bring it by the shop this week? Weekend?

I've also noticed this noise recently but i can only hear it when i am backing up my driveway which is an incline.

I thought this was just the E-brake making this noise? I'm pretty sure ive had this since day one