Notices
Series I Tech Garage The place to discuss anything technical about the RX-8 that doesn't fit into any of the categories below.

Why does my car bog/bounce when shifting?

Thread Tools
 
Search this Thread
 
Rate Thread
 
Old 06-09-2010 | 04:09 PM
  #1  
gareth's Avatar
Thread Starter
Registered User
 
Joined: Jun 2010
Posts: 26
Likes: 0
Why does my car bog/bounce when shifting?

Hey all,

While shifting gears my car really seems to bog/bounce when i release the clutch. Especially when driving it hard. Or, even if I'm coasting in second gear and then hit the gas the car doesn't just go it kind of bounces or stutters. Its like a jerk coming from the driveline. Reminds me of when I was a new driver and couldn't shift smoothly. But that rarely happens to me in other cars and typically sports cars can take harder shifting, no?

I've read about the weak clutch pedal mounting in our cars and I'm wondering if purchasing the race roots reinforcement might help my problem?

Or perhaps my motor mounts are worn and allowing excessive engine movement when the motor is quickly unloaded and then loaded again?
Old 06-09-2010 | 06:33 PM
  #2  
Razz1's Avatar
Mu ha.. ha...
 
Joined: Aug 2004
Posts: 14,361
Likes: 3
From: Cali
A bog won't come from motor mounts. They cause drive line lash.

A bog sounds like you need a tune up. Check for air leaks.

Need more info on your car and maientence history.
Old 06-22-2010 | 04:51 PM
  #3  
Rotary-RX8's Avatar
Girls who drive stick FTW
iTrader: (1)
 
Joined: Mar 2010
Posts: 3,429
Likes: 2
From: Toronto
A little thread ressurection here. I dont wanna make another thread. Yes i have this "problem" too. WHen im coasting, if i tap the gas my car tend to bounce forward. You kind of feel the power. Is this normal ?!
Old 06-22-2010 | 05:18 PM
  #4  
Psylence's Avatar
Back in the family
 
Joined: Sep 2003
Posts: 443
Likes: 0
From: philly 'burbs
The Rx8 has a very "direct" feel... unlike anything else. It is not the easiest vehicle to drive smoothly.
Old 06-22-2010 | 05:25 PM
  #5  
Rotary-RX8's Avatar
Girls who drive stick FTW
iTrader: (1)
 
Joined: Mar 2010
Posts: 3,429
Likes: 2
From: Toronto
That doesnt really answer my question lol . Is that a yes ?
Old 03-20-2012 | 11:31 AM
  #6  
python021's Avatar
Registered User
 
Joined: Mar 2011
Posts: 33
Likes: 0
From: Poughkeepsie, NY
This thread has no real answers and I have the same question.
I'm assuming some mounts or bushings are bad but don't see any evidence, and I've only read about motor mounts going bad.
My issue is that, when in gear, at normal pedal position, if I floor it or release it, the whole car shakes front to back.
Now I'm thinking diff mounts but they look fine, and there are so many bushings in the rear. The also happens when launching.
Old 03-20-2012 | 12:03 PM
  #7  
wcs's Avatar
wcs
no agenda
iTrader: (2)
 
Joined: Feb 2005
Posts: 5,210
Likes: 65
From: Ontario
What year is your car?
Mileage?
Mods?
Auto/Manual?

Last time you did plugs, wires, coils, air filter, Maf Clean, ESS clean?

Compression?

Has this just started? Maybe bad gas?
Old 03-23-2012 | 10:35 PM
  #8  
Shamblerock's Avatar
Registered
 
Joined: Aug 2004
Posts: 1,343
Likes: 0
From: Mississauga, Ontario
Your pushing the clutch in too far when you shift......

The way to avoid that bounce and jerk is to depress the clutch 1/2 way as opposed to all the way and shift quickly. If you press all the way, there is a bit of a delay for the clutch to engage again because all the grab of the clutch is in the first 3 inches of depression....

WCS, you still around with the same white RX8 and Nitro?? Haven't been on here for a few years, but still have my Red 2004 RX8. New Brakes and Suspension which gave me new level of enthusiasm to drive it!!
Old 03-24-2012 | 03:39 AM
  #9  
wcs's Avatar
wcs
no agenda
iTrader: (2)
 
Joined: Feb 2005
Posts: 5,210
Likes: 65
From: Ontario
Originally Posted by Shamblerock
The way to avoid that bounce and jerk is to depress the clutch 1/2 way as opposed to all the way and shift quickly. If you press all the way, there is a bit of a delay for the clutch to engage again because all the grab of the clutch is in the first 3 inches of depression....

WCS, you still around with the same white RX8 and Nitro?? Haven't been on here for a few years, but still have my Red 2004 RX8. New Brakes and Suspension which gave me new level of enthusiasm to drive it!!
Deeeeewwwwwwwd!!!!!!
Longtime no see!
I'm still around however I'm turbo'd now running daily boost of 7.5 psi and top boost of 10.5 psi.
I would like to go higher but I've maxd the fuel pump

When I get back from wales we should go for a beer.
Dark brew and Neo are still kicking around as well.
Old 03-24-2012 | 05:45 AM
  #10  
Shamblerock's Avatar
Registered
 
Joined: Aug 2004
Posts: 1,343
Likes: 0
From: Mississauga, Ontario
WCS, that is too cool...Turboed....beautiful!! Can wait to hook up an catch up. Let me know when you are back in town and we'll hook up for sure and try to get Neo and Dark Brew to join with. Turbo is my next idea but I have so many questions for you before I get my 8 blown.

Safe trip back.

Cheers.
Old 03-29-2012 | 09:22 AM
  #11  
python021's Avatar
Registered User
 
Joined: Mar 2011
Posts: 33
Likes: 0
From: Poughkeepsie, NY
Originally Posted by Shamblerock
The way to avoid that bounce and jerk is to depress the clutch 1/2 way as opposed to all the way and shift quickly. If you press all the way, there is a bit of a delay for the clutch to engage again because all the grab of the clutch is in the first 3 inches of depression....
2004 mt 89kmiles
Its not anything with the clutch, example:
In 3rd, 6k or so, let off gas... the car bounces front to back about 2 times, hit the gas... the car bounces back to front about 2times.
All never touching the clutch.
Old 03-29-2012 | 09:26 AM
  #12  
Arca_ex's Avatar
BECAUSE RACECAR
iTrader: (10)
 
Joined: May 2011
Posts: 1,413
Likes: 8
From: Arizona
Originally Posted by python021
2004 mt 89kmiles
Its not anything with the clutch, example:
In 3rd, 6k or so, let off gas... the car bounces front to back about 2 times, hit the gas... the car bounces back to front about 2times.
All never touching the clutch.
Normal.


Learn how to be smooth when getting on and off the gas, because that's what happens when you load and unload the driveline harshly like that.
Old 03-29-2012 | 05:44 PM
  #13  
Shamblerock's Avatar
Registered
 
Joined: Aug 2004
Posts: 1,343
Likes: 0
From: Mississauga, Ontario
I agree with him ^^. Normal and be a tad gentler with the clutch, not too much, just a tad.
Old 05-24-2012 | 06:36 AM
  #14  
cuadrillas's Avatar
No longer a Celica owner!
iTrader: (1)
 
Joined: Feb 2012
Posts: 37
Likes: 0
From: Sacramento
Its the damn pedal position sensor!
Ok I sound nuts,but Ive taken the sensor,in hand and tested this last night and the night before.
Im ignorant as to its property's. There should only be open,closed.
So,If you remove the green bushing on the clutch pedal,the jerking and jumping and bogging in first and second will stop. Problem is when in forth threw sixth the acceleration will behave as if you're ridding the clutch, also cruz Control will not engage.
Ive spent about a week,made myself look like a fool and cut almost all of my fingers trying to figure this out. Please post if this has (quasi) fixed your issue.
Old 05-25-2012 | 11:18 AM
  #15  
40w8's Avatar
Registered
 
Joined: Apr 2011
Posts: 523
Likes: 7
Originally Posted by python021
2004 mt 89kmiles
Its not anything with the clutch, example:
In 3rd, 6k or so, let off gas... the car bounces front to back about 2 times, hit the gas... the car bounces back to front about 2times.
All never touching the clutch.
I have a 07 6spd auto that I know is running right because I track it and have upgraded to BHR ign and fuel pump.

It is a bitch to pace in rush hour with the accordian nature of starts and stops.

That getting on and off the gas causes the worst surging I've ever seen on a car, so I have to stay back and keep a constant speed while the aggressive drivers fill the gap.

At least you can push the clutch in to stop it.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Dokuji
Series I Trouble Shooting
8
11-01-2016 02:51 PM
akagc
RX-8's For Sale/Wanted
7
08-11-2015 07:07 PM
escapedan
Series I Do It Yourself Forum
3
07-29-2015 10:44 PM
skydemon
RX-8 Parts For Sale/Wanted
5
07-23-2015 01:51 PM
reverse01134
RX-8's For Sale/Wanted
0
07-16-2015 10:27 PM



You have already rated this thread Rating: Thread Rating: 0 votes,  average.

Quick Reply: Why does my car bog/bounce when shifting?



All times are GMT -5. The time now is 10:26 AM.