I have an activa ct 2.0. The one with the broken knock sensor. I also have another gripe. When I start the car up it takes about 30 secs for the STOP lights to go out. I drive off and the back susp. feel hard. After about a minute the back drops down with a thud and the susp. goes o.k. Is 30 secs a reasonable time for the lights to go out.? Why does the back end suddenly drop, and is it easy to fix ?
Its my second Xantia and I love them, big roomy & comfy
Thanks v. much Pat
Thanks for the advice another question please
Moderator: RichardW
Pat -
If the rear suspension suddenly drops and then feels ok after quite some delay - then you have a problem with the system pressure building up fast enough. This is also indicated by the 30sec's STOP light.
What happens is that the system pressure at one point (after some 30sec's) is exactly that large, that the antisink valve opens the rear suspension circuit - and then the presure suddenly equals out.
I would like you to do some very simple tests :
1) Have engine idle, handbrakes on, suspension at normal height.
Now time the click interval from the regulator (pump) - do it bonnet open to clearly hear the clicks.
You should have at least 30seconds ínterval between clicks. To be perfect it should range up in the minutes interval.
If the regulator is clicking constantly - the accumulator sphere is flat (the one on engine block).
2) Same test again - but this time you deliberately set the suspension to the LOWEST setting. This will block off hydraulic supply to all suspension - thus any pressure leaks (internal) here does not influence main system pressure.
Again you should have at least 30seconds click interval.
If a constant clicking from test 1 now seems to calm down - then you have a problem in the suspension circuit.
If the rear suspension suddenly drops and then feels ok after quite some delay - then you have a problem with the system pressure building up fast enough. This is also indicated by the 30sec's STOP light.
What happens is that the system pressure at one point (after some 30sec's) is exactly that large, that the antisink valve opens the rear suspension circuit - and then the presure suddenly equals out.
I would like you to do some very simple tests :
1) Have engine idle, handbrakes on, suspension at normal height.
Now time the click interval from the regulator (pump) - do it bonnet open to clearly hear the clicks.
You should have at least 30seconds ínterval between clicks. To be perfect it should range up in the minutes interval.
If the regulator is clicking constantly - the accumulator sphere is flat (the one on engine block).
2) Same test again - but this time you deliberately set the suspension to the LOWEST setting. This will block off hydraulic supply to all suspension - thus any pressure leaks (internal) here does not influence main system pressure.
Again you should have at least 30seconds click interval.
If a constant clicking from test 1 now seems to calm down - then you have a problem in the suspension circuit.