Injector Pump damper, Help please.

paranoid · Unread post by **paranoid** » 20 Jun 2005, 01:28

Been out all day, car very warm, when at a standstill the revs take ages to return to tickover staying at about 1500 rpm.
I think I have tracked it down to the strut on the injector body(looks like a small tailgate strut) very worn on one side and something not right about the movement.
Any ideas if its anything else!!!!!!!!
Have put a request in the for sale for an old one!!!

wheeler · Unread post by **wheeler** » 20 Jun 2005, 01:40

to be honest you would be better just taking it off & throwing it away,it doesent do anything else.

NiSk · Unread post by **NiSk** » 20 Jun 2005, 02:34

Agree with wheeler - bin it!
//NiSk

Kowalski · Unread post by **Kowalski** » 20 Jun 2005, 03:14

That same throttle damper on mine gave problems, so I popped it off its little balls, oiled them up and put it back together and it behaves itself much better now.
I've not heard anybody else recommend keeping the damper on, it is dangerous to have a sticking accelarator so if oiling the balls doesn't fix it absolutely, bin it as suggested above.

CommY · Unread post by **CommY** » 20 Jun 2005, 04:22

I bet your cable has frayed and is sticking. Don't know how much a genuine Cit one is but you can buy a universal cable for about £15

Unread post by **citroenxm** » 20 Jun 2005, 17:49

Not the cable. I hedge bets more on the damper strut as above. Seen a few with these missing off the pumps. They worked perfectly before on older cars without them. So why have more to go wrong.......

Kowalski · Unread post by **Kowalski** » 20 Jun 2005, 17:55

The damper is there to stop you being able to open the throttle as quickly, it gives the turbo a bit more of a chance to provide some boost before the fueling comes in so it will (in theory) clean up emissions slightly. In practice, I don't think it does a whole lot apart from slow your car down.

fastandfurryous · Unread post by **fastandfurryous** » 20 Jun 2005, 18:12

The damper doesn't stop you standing on the accelerator any quicker. What it does do is to prevent the accelerator lever from smapping back to idle. Because it damps the speed at which the engine can go from on-load to off-load, there is less driveline shunt, and hence softer engine mountings can be used.
If the damper is removed, it may well be possible to shunt the engine&gearbox with abrupt accelerator movements, and cause some really jerky driving. Obviously if you drive gently this isn't a problem, but I have found that it makes full-power gearchanges much smoother if the damper is fitted.

paranoid · Unread post by **paranoid** » 20 Jun 2005, 21:11

Took damper off and it's absolutly shot, push ends together and it doesn't return, damping all gone.
So in the bin it has gone,I was expecting a short amount of getting used to the throttle again but it seems a bit better due the binding now being gone.

Kowalski · Unread post by **Kowalski** » 20 Jun 2005, 22:44

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by fastandfurryous</i>

The damper doesn't stop you standing on the accelerator any quicker.<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
It does, but not on it's own. There is a spring inline in the accelarator cable that gets compressed when you stamp on the accelarator, so between the two of them the lever on the fuel pump moves more slowly. Admitadly the spring only provides about 1cm of compression and if you adjust the cable so that the spring gets compressed at full accelarator stomp its effects are completely negated.

fastandfurryous · Unread post by **fastandfurryous** » 21 Jun 2005, 01:19

Not all models have this inline spring. Certainly 405 1.9TD models have the damper to reduce driveline shunt (they have the softer mountings) but don't have the inline spring. 406 models do have the spring, but as you say, it's effect is negligable.
I notice also that later 406 and Xantia models have yet another damper, mounted on the opposite side of the pump to the damper strut, which completely over-damps the last few degrees of accelerator travel. No doubt these models have even softer engine mountings, hence the reduced levels of vibration transmitted from the engine. Clever idea, but it does feel odd on the accelerator pedal if you're not used to it.
At the risk of wearing out the engine mountings at an increased rate, I would have said it was best to have the strut-damper fitted. It makes the car smoother anyway, so well worth having. I don't believe they are expensive, certainly cheaper and easier to fit than engine mountings.

Kowalski · Unread post by **Kowalski** » 21 Jun 2005, 02:11

Both of my Xantias have the second damper, but only the newer one has the strut, both are Bosch pumps, the newer one has electronics where as the older one does not.
I had assumed that the second damper was standard on all turbo models and not fitted to non-turbos (mostly because Haynes says its so) but what dampers do the Lucas ones come with (the strut is a Bosch part)?

fastandfurryous · Unread post by **fastandfurryous** » 21 Jun 2005, 02:22

Interesting, as the 405 1.9TD only has the strut, and not the second damper.
I have yet to see a 1.9TD engine with a lucas injection pump, so I have no idea what damping they use (if any). The only engines I've seen with lucas pumps are atmo and 1.7TD engines (with no damping).

john alexander · Unread post by **john alexander** » 21 Jun 2005, 05:28

previous owner of my xantia spent over £100 getting a new strut fitted.It came off at one end shortly after I bought it jamming the throttle open,my son nearly went through a field.Needless to say it was binned .I spoke to an engineer at Bosch who told me that the strut was fitted because at certain road speeds the throttle bounced.Hope this helps john

shezads · Unread post by **shezads** » 23 Jun 2005, 22:02

My zx doesnt have the damper on, but my brother 306 does. They both have the bosch pump, mine is a 94 td, his is a 95 td both on m plates. My brothers accelerator seems more responsive (the ne with the damper) - but when coming off the accelerator - at low speeds - car tends to jerk.
My car on ther other hand (without the damper)- accelerator does not seem to be as responsive but does not have the jerkiness on light throttle either.