Ls400 Nitrogen Accumulator, How Does It Work? How To Regas?

[Z2TT]

Hello,

On the LS400/Celsiors there is a Nitrogen accumulator and pump, I don't know how it works but there is a line going from the nitrogen canister itself

to one of the ABS Units, what is this for?

I know on some Soarers, the Nitrogen accumulator is used to assist in braking, so that is why it is placed near the master cylinder, using nitrogen to help

push the cylinder.

But in the LS400/Celsiors the Nitrogen accumulator is by itself, has has a hard pipe going from there all the way to one of the ABS

units near the air filter.

I have been getting Error 19 "Pump cycling too often" which means low on nitrogen, and at this point the ECU is limiting power/preventing kickdown

which is some sort of failsafe mode to prevent excessive acceleration.

I believe it's something to do with either Traction control or ABS.

Does anybody have more knowledge on the exact function of this Nitrogen accumulator in the Celsior/LS400, and how to go about getting it fixed/regassed?

Thanks.

[steve2006]

Hi firstly welcome to the LOC.

The nitrogen cylinder provides the traction control system with the required pressure to operate the rear brake hydraulics when the TC is operating and also the ABS modulation,mine has the same problem albeit on a intermittent basis at the moment.

What tends to happen is after a short time the Trac light comes on and as you have correctly diagnosed produces code 19 Trac pump operation too long.

There have been reported successes by opening the bleed nipple on the Trac accumulator with the ignition on and bleeding the system then doing the same on the ABS block but I think the outright cause is low pressure in the accumulator possibly due to leaking seals so the pump tries to compensate by staying on too long.

I have found a company in Leicester who say they may be able to repair/recharge the accumulator but have not yet had the time to remove the thing which would mean having the car off the road.

I haven't noticed any other problems with kick down etc when the light comes on.

There is a Celsipr being broken not far from me and I am considering getting the accumulator off this and fitting to mine then seeing about the repair of the original.

Once the snow clears I will get it done and then come back with the results.

UK spec cars are not fitted with TC and also no troublesome EGR pipe to worry about.

BTW are you in Perth Australia? If you are have a read on the link below for more local places to you for recharging/repair

http://soarercentral.com/sc-forum/messages/9739/166885.html