Not having had the Xantia for long, I find that occassionally when stopped at lights and foot on the brake, I put it into 1st gear, take my foot off the brake, and then the back end drops then rises again slightly as I take off. The interesting thing is this does'nt happen all the time!
Any comments to put my mind at rest?
Other that that the car is brilliant.
Thanks,
Jim Ioannidis
97VSX
Melbourne, Australia
Is this normal for a Xantia?
Moderator: RichardW
-
Black97Xantia
- Posts: 3
- Joined: 01 May 2003, 10:49
- Location: Australia
- My Cars:
-
Dave Burns
- Posts: 1915
- Joined: 14 May 2001, 05:30
- Location: United Kingdom
- My Cars:
- x 2
Completely normal Jim, it has to do with the rear suspension geometry and the atomatic ride height adjustment.
This usualy occurs if you have to stop abruptly and only then if you keep the foot brake on, such as when the lights change as you approach them, rather than in your own time so to speak.
The car's mass is transfered more to the front during breaking as is normal for any vehicle, this will produce a dip in the suspension at the front and raise it slightly at the back.
If you keep your foot on the brake this prevents the rear suspension from returning to its normal position because to do this the wheel must roll slightly, this results in the height corrector valve being opened to compensate for the now higher state of the rear suspension.
With the valve open, oil is expelled from the rear spheres but because the wheel can't rotate because of the foot brake, the valve doesn't get the required motion from the roll bar to close it again.
As soon as you release the brake the rear wheels rolls and the suspension drops because now there is insufficient oil present in the rear circuit to maintain correct heigh, this as you are aware of is quickly replaced and the ride height restored.
The amount by which the rear drops depends on how hard you keep the brake pressed and the length of time you are stationary.
Dave
This usualy occurs if you have to stop abruptly and only then if you keep the foot brake on, such as when the lights change as you approach them, rather than in your own time so to speak.
The car's mass is transfered more to the front during breaking as is normal for any vehicle, this will produce a dip in the suspension at the front and raise it slightly at the back.
If you keep your foot on the brake this prevents the rear suspension from returning to its normal position because to do this the wheel must roll slightly, this results in the height corrector valve being opened to compensate for the now higher state of the rear suspension.
With the valve open, oil is expelled from the rear spheres but because the wheel can't rotate because of the foot brake, the valve doesn't get the required motion from the roll bar to close it again.
As soon as you release the brake the rear wheels rolls and the suspension drops because now there is insufficient oil present in the rear circuit to maintain correct heigh, this as you are aware of is quickly replaced and the ride height restored.
The amount by which the rear drops depends on how hard you keep the brake pressed and the length of time you are stationary.
Dave
-
Black97Xantia
- Posts: 3
- Joined: 01 May 2003, 10:49
- Location: Australia
- My Cars:
-
Dave Burns
- Posts: 1915
- Joined: 14 May 2001, 05:30
- Location: United Kingdom
- My Cars:
- x 2
<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by mbunting</i>
Is he a super-guru geek or what ?
Mat.
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
Hello Mat. does something displease you.
Dave
Is he a super-guru geek or what ?
Mat.
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
Hello Mat. does something displease you.
Dave