Xantia jerking

[cc101]

Hi all, another question! I've a 1994 1.9 TD with a bosch pump, when I lift off the accelerator in say 3rd gear, the car kangaroos, it drives perfectly other than when u lift off the throttle.

Thanks again for all the help,

Chris.

[CitroJim]

Interesting one Chris. I've known it on a Lucas pump but never on a Bosch pump. I'm thinking...

Does the car start with ease and run well in other respects?

[Mandrake]

Is there a good old fashioned dash pot on the throttle that slows sudden throttle closing on the 1.9TD ?

[CitroJim]

Is there a good old fashioned dash pot on the throttle that slows sudden throttle closing on the 1.9TD ?

Yep, there is. Two in some cases. Good thinking Simon

If your pump has what looks like a miniature black shock-absorber on the front of the pump with one end attached to the throttle lever then remove it, throw it in the bin and see if it's any better. There is also another damper at the back of the pump that does look more like a dashpot. This one though is essential as it executes the anti-stall function and without it the engine will stall on the over-run.

The black shock absorber I spoke of earlier can cause the problem and the car is better off without it. It was originally there as an emissions device to regulate throttle opening speed and therefore smoke emissions...

[Mandrake]

If theres a damper that is supposed to slow down closing (not opening) of the throttle, won't taking it out and throwing it away make it worse ?

[cc101]

Thanks guys, Jim the car starts good and runs very well, it does seem to do it more when warmed up. Will take a look at the pump Simon.

Thanks again.

[CitroJim]

If theres a damper that is supposed to slow down closing (not opening) of the throttle, won't taking it out and throwing it away make it worse ?

No, the anti-stall damper is only operative near the very end of the throttle travel whereas the black one is operative both-ways over the whole travel. It is a hindrance rather than a help and throwing it away sharpens the throttle response into the bargain...

[Chlorate]

That silly damper thing is the first thing I thought of when I read your symptoms it's probably getting a bit sticky, I have no idea why the damn thing was fitted to begin with. Well worth removing even if it isn't causing your trouble

Alex

[CitroJim]

absolutely Alex

Here's the reason as I posted earlier in the thread...

It was originally there as an emissions device to regulate throttle opening speed and therefore smoke emissions...

[Chlorate]

Which is odd because it seems to work more the other way, I only really noticed that the pedal took time to come back to zero. But anyhow it's very easy to remove.