Hydraulic Wierdness

mattpc · Post by **mattpc** » 23 Dec 2004, 04:32

Recently had all the spheres done on my 94 TDSX at Westroen. Worked a treat and the car feels really nice. However, I've started the car twice today and the stop light has stayed on for about 3 seconds after starting the engine and then gone out. Then when I've lowered the car to minimum height and raised it again the stop light has not come on at all (usually it goes on, flickers and goes out). Ideas anyone?

PeterMann · Post by **PeterMann** » 23 Dec 2004, 07:06

Could it be that you are not used to having a fully charged accumulator ?

NiSk · Post by **NiSk** » 23 Dec 2004, 12:50

Give it a good Citrobatics exercise - you've evidently still got some air in the system.
//NiSk

uhn113x · Post by **uhn113x** » 23 Dec 2004, 13:18

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by mattpc

Recently had all the spheres done on my 94 TDSX at Westroen. Worked a treat and the car feels really nice. However, I've started the car twice today and the stop light has stayed on for about 3 seconds after starting the engine and then gone out. Then when I've lowered the car to minimum height and raised it again the stop light has not come on at all (usually it goes on, flickers and goes out). Ideas anyone?
<hr height="1" noshade id="quote"></blockquote id="quote">
Is there actually anything wrong with the car? Sounds good to me!

mattpc · Post by **mattpc** » 23 Dec 2004, 14:31

The suspension seems to be working well. It's just unusual behaviour from the stop light. Usually it goes out as soon as I start the car and it always used to come on if i lowered the car to min height and then put it back up again. Just wondering if what is happening now is normal or whether there is cause for concern?

broomie · Post by **broomie** » 23 Dec 2004, 14:40

What you describe is normal for an accumulator in good condition - be happY!

np · Post by np » 23 Dec 2004, 15:05

My stop & brake light do the same thing on start up.Only when its been sitting fore more than a few hours.Never did it before i had the rear height corrector & accm sphere replaced.LHM level fine,& everything works as it should.

Dave Burns · Post by **Dave Burns** » 23 Dec 2004, 16:13

Lower the car to minimum and let it tick over for two minutes, then raise the lever and see if the stop light comes on.
Dave

mattpc · Post by **mattpc** » 23 Dec 2004, 16:30

lowered the car to a min for about five mins last night and then raised it. Still no stop light. However, suspension feels good so I don't think I'll worry about it..

jeremy · Post by **jeremy** » 23 Dec 2004, 17:58

My guess is that your accumulator has lost a little pressure. This means that when the car starts it stretches the diaphragm a little more hence the light coming on for 3 secs. The converse is that the acumulator probably holds a little more high pressure LHM - so light doesn't come on when you raise the car.
I suppose it could be temperature related too. A drop in temperature will lower the accumulator pressure a bit as well.
If everything seems to be working well then its nothing to worry about and indeed seems to be normal to excellent.
jeremy

alexx · Post by **alexx** » 23 Dec 2004, 22:25

mattpc, what you described is normal for an accumulator in good condition
With flat accumulator, stop light will go off instantly after starting the engine, since there's no nitrogen inside it to be compressed

mattpc · Post by **mattpc** » 23 Dec 2004, 22:43

That's cool, my mind is more at rest now. Thanks for your help guys.[:)]

dan.2cv · Post by **dan.2cv** » 24 Dec 2004, 00:45

Well hold on a minute, why does mine stay on for about 20 secs when I start up? I replaced the acc sphere a short while ago, so It can't be flat yet. In fact the light stays on for longer on start up since I replaced it, which I thought was right because of the nitrogen pressure?
Am I completely wrong? Is my car sick?

wonderd · Post by **wonderd** » 24 Dec 2004, 01:08

could it be your high pressure pump not providing enough pressure?
does the car raise quickly enough?

alexx · Post by **alexx** » 24 Dec 2004, 01:37

Well, let me explain.
In fact, you can determine approximate pressure in the accu sphere measuring the time from engine start to the moment, when the check light goes off, and doing some math (provided that HP pump is in good condition). You need to:
1) release the pressure in the sphere by the screw on the regulator, or leaving the car overnight (it's usually enough)
2) move the height lever to the lowest position, so that HP pump will pressurise accu sphere only
With new or renewed sphere, it should be about 5 sec on petrol and about 3 s on the diesel engine (except on Activa, where there are other two spheres connected to the regulator) - for the cars with anti-sink and 6+2 pump. This time is needed to raise the pressure in the sphere from 62 bar to about 90 bar, when the ligh goes off, by filling the LHM in the sphere. If the pressure in the sphere is lower, more time is needed. Except, of course, in the case the sphere is completely (or almost) flat and there is no nitrogen inside.
With height lever in the normal position, this time could be longer, because other spheres will be topped up (it depends whether anti-sink valves open before the light goes off or not).