Thread: Do not expect EAS to work off road on D4

Well, the good raising time didn't last very long as over the last week or two, raising from access to normal height has been taking several minutes. New suspension ecu software to reduce the reservoir pressure has made it even worse, whereby after a few hours of driving it still took far too long for it to regain normal height. I'll hook-up the Faultmate to check the reservoir pressure but I suspect the dessicant in the dryer on this new compressor has expanded due to the moisture that's around again and because of the excessively-strong spring, the dessicant is now too compressed to allow the air through at a decent rate. I'm going to try to remove the dryer without removing the compressor. This time I'll see if I can get it fixed properly before this compressor is also destroyed.

Graeme,
how did you go removing the dryer without removing the compressor, possible? I'd like to check mine as the compressor seems to run for a long time after raising the vehicle and I've recenty had the suspension warning lights come on occasionally after using the EAS

thx,
Ashes

Yes, the dryer can be extracted without removing the compressor assembly. With the lower cover removed (unclip the air-lines at the rear before attempting to extract the cover), a stubby Phillips head screwdriver easily undoes the retaining screw.

The dryer wasn't particularly restrictive, so either there's a leak somewhere between the compressor and the rear valve blocks (front has been checked) or a valve in the compressor itself isn't closing properly.

I finally got around to having another look for the cause of the slow rising. The problem is now fixed with the vehicle once again rising quite quickly.

Recently I had cause to look at suspension system fault codes and found one for the reservoir valve although I was not aware of any console message having been issued. Anyway, the cause was a poor electrical connection at the suspension ecu, so nothing to do with the compressor itself and I was very pleased with that.

I did not expect that a non-functioning reservoir valve would cause such slow rising but now understand why multiple off-road height activations would quickly slow if the reservoir didn't get a chance to refill properly.

How did you get the valve to work again? Where are they located? Mine rises slowest on the front, is that normal?

Originally Posted by adzee

How did you get the valve to work again? Where are they located? Mine rises slowest on the front, is that normal?

Don't know about normal....but lots do it! I think somebody was once told that it was to stop glaring other vehicles when the headlights are on....but, I don't know the truth. Probably just a case of pumping two coils at a time.

Cheers,

Kev.

The front always rises to its full height last. Both usually start to rise at the same time but when the reservoir runs low on pressure, the compressor by itself is much slower and the rear completes long before the front does. Changing heights frequently doesn't give the reservoir chance to fill properly so the front being slow to rise is seen more often.

Edit: The front valve block has larger orifices than the rear in an attempt to get the heavier front to rise at about the same rate. Perhaps with a suitably heavy load in the rear the front would rise at the same rate.

I think it maybe designed to raise the back first and lowerr the front first to stop the lights blinding oncoming traffic when changed.