follow ft86club on our blog, twitter or facebook.
FT86CLUB
Ft86Club
Delicious Tuning
Register Garage Community Calendar Today's Posts Search

Go Back   Toyota GR86, 86, FR-S and Subaru BRZ Forum & Owners Community - FT86CLUB > Technical Topics > Issues | Warranty | Recalls / TSB

Issues | Warranty | Recalls / TSB Problems, issues, recalls, TSBs


User Tag List

Reply
 
Thread Tools Search this Thread
Old 08-14-2014, 02:22 PM   #1
kdbar
Member
 
Join Date: Jul 2014
Drives: Dark Grey BRZ
Location: Irvine, CA
Posts: 37
Thanks: 4
Thanked 2 Times in 2 Posts
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
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!
kdbar is offline   Reply With Quote
Old 08-17-2014, 10:33 PM   #2
wmak
Member
 
Join Date: Jul 2014
Drives: Series Blue BRZ
Location: California
Posts: 21
Thanks: 3
Thanked 1 Time in 1 Post
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
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.
wmak is offline   Reply With Quote
Old 08-18-2014, 12:00 AM   #3
puravida
Member
 
Join Date: Sep 2013
Drives: 14 brz, 97 nsx, 85 land cruiser
Location: so'cal
Posts: 31
Thanks: 16
Thanked 3 Times in 3 Posts
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
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
puravida is offline   Reply With Quote
Old 08-18-2014, 01:48 AM   #4
pantdino
Senior Member
 
Join Date: Jul 2014
Drives: Firestorm 2013 FR-S
Location: Cerritos, CA
Posts: 265
Thanks: 7
Thanked 95 Times in 57 Posts
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Garage
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.
pantdino is offline   Reply With Quote
The Following User Says Thank You to pantdino For This Useful Post:
puravida (08-18-2014)
Old 08-18-2014, 10:47 AM   #5
civicdrivr
Senior Member
 
civicdrivr's Avatar
 
Join Date: Mar 2012
Drives: 2018 Golf R
Location: Richmond, VA
Posts: 2,807
Thanks: 5,386
Thanked 1,095 Times in 647 Posts
Mentioned: 68 Post(s)
Tagged: 7 Thread(s)
Could it possibly be the transmission mount?
__________________
Parting out HERE
civicdrivr is offline   Reply With Quote
Old 08-18-2014, 11:37 AM   #6
wmak
Member
 
Join Date: Jul 2014
Drives: Series Blue BRZ
Location: California
Posts: 21
Thanks: 3
Thanked 1 Time in 1 Post
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
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).
wmak is offline   Reply With Quote
Old 08-18-2014, 11:46 AM   #7
evo4g63
Senior Member
 
evo4g63's Avatar
 
Join Date: Jan 2013
Drives: 2016 Subaru WRX
Location: Phoenix, AZ
Posts: 979
Thanks: 235
Thanked 329 Times in 231 Posts
Mentioned: 33 Post(s)
Tagged: 0 Thread(s)
Sounds like tip in knock to me.
__________________
-2016 Subaru WRX
-2013 Scion FR-S: Wastegated Vortech V3'd, E85 SOLD
evo4g63 is offline   Reply With Quote
The Following User Says Thank You to evo4g63 For This Useful Post:
puravida (08-18-2014)
Old 08-18-2014, 11:58 AM   #8
wmak
Member
 
Join Date: Jul 2014
Drives: Series Blue BRZ
Location: California
Posts: 21
Thanks: 3
Thanked 1 Time in 1 Post
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
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?
wmak is offline   Reply With Quote
Old 08-18-2014, 12:23 PM   #9
JB86'd
Senior Member
 
JB86'd's Avatar
 
Join Date: Oct 2013
Drives: JAWS
Location: socal
Posts: 703
Thanks: 753
Thanked 437 Times in 224 Posts
Mentioned: 27 Post(s)
Tagged: 1 Thread(s)
Quote:
Originally Posted by wmak View Post
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.
__________________
JB86'd is offline   Reply With Quote
The Following User Says Thank You to JB86'd For This Useful Post:
puravida (08-18-2014)
Old 08-18-2014, 12:25 PM   #10
wmak
Member
 
Join Date: Jul 2014
Drives: Series Blue BRZ
Location: California
Posts: 21
Thanks: 3
Thanked 1 Time in 1 Post
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quote:
Originally Posted by JB86'd View Post
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.
wmak is offline   Reply With Quote
Old 08-18-2014, 01:46 PM   #11
puravida
Member
 
Join Date: Sep 2013
Drives: 14 brz, 97 nsx, 85 land cruiser
Location: so'cal
Posts: 31
Thanks: 16
Thanked 3 Times in 3 Posts
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
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 !!
puravida is offline   Reply With Quote
Old 08-18-2014, 01:51 PM   #12
evo4g63
Senior Member
 
evo4g63's Avatar
 
Join Date: Jan 2013
Drives: 2016 Subaru WRX
Location: Phoenix, AZ
Posts: 979
Thanks: 235
Thanked 329 Times in 231 Posts
Mentioned: 33 Post(s)
Tagged: 0 Thread(s)
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.
__________________
-2016 Subaru WRX
-2013 Scion FR-S: Wastegated Vortech V3'd, E85 SOLD
evo4g63 is offline   Reply With Quote
Old 08-18-2014, 05:57 PM   #13
King Tut
NASA SpecE30 Racer
 
King Tut's Avatar
 
Join Date: May 2012
Drives: 2006 Honda S2000
Location: Gulf Breeze, FL
Posts: 7,279
Thanks: 607
Thanked 5,759 Times in 3,055 Posts
Mentioned: 274 Post(s)
Tagged: 10 Thread(s)
Send a message via AIM to King Tut
We talking manuals or automatics in here?
__________________
King Tut is offline   Reply With Quote
Old 08-18-2014, 06:02 PM   #14
puravida
Member
 
Join Date: Sep 2013
Drives: 14 brz, 97 nsx, 85 land cruiser
Location: so'cal
Posts: 31
Thanks: 16
Thanked 3 Times in 3 Posts
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quote:
Originally Posted by King Tut View Post
We talking manuals or automatics in here?
Manual …
puravida is offline   Reply With Quote
 
Reply


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
High RPM 3rd to 4th Shift Crunch calmtigers Issues | Warranty | Recalls / TSB 1 08-01-2014 07:08 PM
6th to 5th Downshift Crunch jcat5150 Issues | Warranty | Recalls / TSB 1 04-17-2014 03:41 PM
Second Gear Crunch? NOHOME Scion FR-S / Toyota 86 GT86 General Forum 18 09-27-2012 02:52 PM
5th Gear and 6th Gear 0% throttle to 80% throttle gear crunch? kharn83 Issues | Warranty | Recalls / TSB 9 08-06-2012 07:44 PM


All times are GMT -4. The time now is 10:55 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
User Alert System provided by Advanced User Tagging v3.3.0 (Lite) - vBulletin Mods & Addons Copyright © 2024 DragonByte Technologies Ltd.

Garage vBulletin Plugins by Drive Thru Online, Inc.