Can ACE raise the front of a Discovery 2? Or just airbags lowering rear?

[MAF Diver]

I've got ACE and SLS (airbags) in my D2a V8 4L and I've noticed two things when stopping at traffic lights:

1) Sometimes it looks like the front is raising but obviously that can't be since it's got coils, right? Or can ACE do this?

I assume it's the SLS lowering the airbags in the back. Is that normal? Does yours do it too? Or is it a sign that the SLS is failing?

(I had the rear drop completely to the very lowest setting the other day when driving on a lot of curves and speed bumps. It then raised up later and I've never found it sagged in the morning.)


2) Sometimes shortly after braking to stop in traffic, the front will jolt up very quickly like it's getting unstuck from something.

Is that an issue with shocks (probably the original ones still, after 75,000 miles on the clock), coils, or is it something to do with ACE? Danger?

[simonmelb]

I have ACE and SLS.

Yes it’s normal for the SLS to adjust height sometimes when stopped at the lights etc. So looking over the bonnet it can appear like the front is changing height, which it’s not.

No sudden movements from or rear should be felt so something isn’t right there!

[Tins]

Correct me if I'm wrong here, but I always believed ACE would correct from side to side, not front to rear.

SLS will definitely respond to braking etc as the height sensors move.

[V8Ian]

ACE is simply an hydraulicly, self adjusting/reactive sway bar.

[loanrangie]

It can't raise the front as there is no device to raise it, only the rear bags can be adjusted.

[MAF Diver]

Thanks everyone!

OK, so sounds like SLS might be a bit buggered?

But ACE has no part in it, right? (How does one troubleshoot ACE to know if it's actually fully working? Or is only semi-working?)

For troubleshooting SLS:
1) I'll spray some soapy water onto the airbags? They don't lower when left unused for a few days, so not sure how this can help.
2) But how can I check if it's maybe malfunctioning sensors?

I'll add:

That 'pop' that I sometimes get feels like something getting loose. Like a coil/shock or some other part? But shocks aren't leaking and a mechanic in Sydney did the upper ball joints a month ago and had a look then. But I wasn't getting that pop back then, it's pretty recent.

But yeah, maybe it's the airbags dropping a few mm for whatever reason, but both at the same time like that?

[V8Ian]

Any problems with ACE should illuminate the amber light, bottom left of the instrument cluster.
Have you got a Nanocom?

[MAF Diver]

Thanks for the replies! No Nanocom and no dash lights luckily.

For the jolt that I get, I wonder if it could be my shocks or springs? Or airbags too?