Xantia MK2 – “Bang” from left calliper when braking

[lancia58]

Hi

Recently when I rapidly pumping the braking pedal ( for almost all its travel ) at slow speeds 5Km/h, I can hear and feel a “bang” from the left calliper. In addition the steering wheel turns a bit to the left. I just fixed a leakage from the left calliper and installed new brake pads . After this for couple of days the “bang” disappeared but now it is back. The “bang” is not happened when braking normally with gradual pressure on the brake pedal.
I checked both wishbones bushes and all bushes are OK. One thing I know is that the steering ram bushes are worn, I going to change them next week but logically it does not look related to the problem.
Any idea what can be the source to the “bang” ?

The car is Xantia MK2 2.0 16V automatic make year 2000.

Thanks
Zohar

[taffy]

are the springs bacl on the caliper?ive made that mistake i left themoff by mistake
also front wishbone bush can wear and move inside the arm..also bottom balljoint..
i would check ur work agian just to be 100% sure...

[lancia58]

The “bang” was before I changed the brake pads. As I mentioned after fixing the leak and install the new brake pads for couple of days the “bang” disappeared. I checked the ball joints and they are OK.

Thanks
Zohar

[lancia58]

Any ideas ?

Thanks

[Stempy]

I had an issue once where the ARB was clouting the lower arm so it might be worth looking for signs of contact there.

[taffy]

does it also do it sometimes when u pull off?

[taffy]

from what u say if its pulling to the left i would check passinger side front wishbone bush...go for a drive and get it to make the bang and stop the car...turn steering and check for a gap infront of the font bush in the mounting brackets..the arm could have moved over the bush allowing movement and the bang would be it giving way and slaming backwards in to the bracket under force from the wheels going towards the back of the car under brakeing...its worth a check its happened to me...also u would see the p bush distort inwards a bit too

[isisalar]

If it's not a loose caliper or disc, sounds like one or other of the wishbone bushes have gone. Well worth using genuine parts for replacement, there are some really poor quality copies out there and the OE ones are not that expensive, P bushes about £30 copies about £20, non OE fron GSF about £8, how good can they be for that?
Cheers
Paul

[lancia58]

Hi

The none P bush are genuine, for the P bush I used Topran which are made in Germany and of a very good quality. Anyway I lifted the car at a local garage and checked the bushes and all are OK. I found out the ABR bushes are worn so ordered Delphi ones. I do not think that the worn ABR bushes are the cause, but before continuing to look for the cause I'll change them.

Thanks
Zohar

[taffy]

what about the wheel bolts?
any change in wheels or bolts?
sometimes alloy and steel wheels have different depths
and the bolts can be too long behind the disc..
might cause a bang if wheel bearing failing
also subframe bolts loose?
but also ur car pulls to the left..

[falling-out-with-my-car]

My S2 does this occasionally moving forwards after I have been reversing into the driveway I think it is akin to the changing of direction of the wheels and dependant upon how hard you hit the brake pedal I noticed you did say something in your post about how hard you brake gently and progressively doesn't make the sound, I think the thick paint on the modern pads wears off or chips off allowing some slight sideways movement of the pads maybe only 1 or 2mm each side when changing direction backwards or forwards. you did say the bang went away for a couple of days when you put new pads in presumably with fresh paint on them.
The pulling to one side could be a seized calliper or the camber of the road I have noticed my Xantias ability to follow the camber occasionally on the A14, if you have installed new pads recently the position of the piston once it has been wound back to install the new pads may be wrong the groove as I understand it has to be the right way up for the piston to act upon the pads correctly. I once got it wrong and my piston wasn't acting on the pads properly. Causing the car to pull to the other side when braking. How tight is your hand brake adjuster on top of the calliper, is it under tension all of the time? if so the braking effort may be stronger on one side than the other causing some pulling on the steering. I had a constant argument with my MOT station about tension on the handbrake cable they said that the tension on the cable should pull the handbrake lever down all the way down but this is not true according to Citroen in Slough who confirmed that the handbrake lever was slack at the bottom of its travel owing to a modification on MK1 Xantias where the first two teeth on the handbrake quadrant were ground off because the handbrake was slipping, so when lifting the handbrake it should not grab the cable immediately there should be a slight slackness before the cable is pulled, otherwise the cable may be to tight closing the sprung calliper adjusters causing to much effort on one side or the other. It is important to have a little slack in the handbrake cable to ensure that the sprung adjuster on top of the calliper is not acting on the pads at all times.
Apparently the modification/recall occurred when a MK1 was parked on a hill in Southampton for the night by the morning it had travelled down the hill and hit a petrol station which is why I always park in gear especially on a hill .