More Trouble Active Suspension

[lynneandcrow]

Hi there I have a problem that I can not Diagnose I have been to X3 Mecanics all with diferent ideas, all expensive of course.

 

The problem is the front left side of the car is bobbing up and down in time with the LHM pump going on, it go's up and then slowly lowers over 7 seconds then repeats on and on WHILST PARKED. Also whilst taking a corner the front left colapses then comes up after the corner. This dose not happen taking a left hand corner. SO..........

 

The first Mechanic (Citr**n) said it was my Regulator unit and would have to be replaced including all wiring costing me over 1000 quid.

 

The Second (West***N) Said its a common problem called bobbing and was due to a faulty strut. This seams the most plausable to me as I have seen the blueprint for the strut and also would explain my previous problem of the return pipe bursting due to high presure LHM passing through it.

 

The Third (Independant) said it was the front active anti roll ram.

 

Who do I belive as I am not speding all the money to do all for obvious reasons Which one of them is buzzing glue??????

 

Please help I need advice and experiance A.S.A.P as I have the chance of getting a Front Strut this Friday and they are realy hard to get..

[techbod]

seen that happen with the C5 a while back it was doing press ups on its own, I only have a theory for it and put it down to electrical short or bad earth because his car was switched off and no one was in the car which means the system was going live and turning off hence it going up and down on its own,

I don't think the strut would do that more like and electrical contact on the height stabilizer

[kfk]

The only reason the vehicle is going to bob up and down in this fashion would be due to the hydraulic ram being supplied with fluid which upon entering the ram causes the movement due to pressure build up and then for the pressure to be lost.

 

Assuming there are no external leaks here are some possibilities:

1, internal leak of the ram

2, height corrector fitted across the car malfunctioning/out of adjustment - but this would probably cause the opposit rear suspension leg to do the same

3, ther rigidity regulator failed and possibly leaking internally causing loss of pressure - again i would guess this would cause a problem with the opposing rear suspension aswell.

 

As far as electronic defects are concerned the only part of the 'active' suspension to be electronic is a solenoid on the rigidity regulator.....However, this is controlled by the hydroactive suspension ecu......this ecu can have its fault codes read and will give indication if the rigidity solenoid is recieving a signal.

 

My guess....and it is a guess would be a problem with the linkages or adjustment problems on the height corrector across the vehicle.

[techbod]

well worth a read

 

http://images.google.co.uk/imgres?imgurl=h...l%3Den%26sa%3DN

 

if you were close to the boro I could have put my diagnostic on the car

 

http://www.quinophex.org/car/suspension.html