Rear suspension.

[J L Carr]

Hi to All.
Having problems with my rear suspension as it keeps on dropping after I park up and then I have to sit for 5 mins waiting for it to pump back up. If I leave it a few days the whole lot drops, it had new air bags 2 years ago checked around for leaks but cannot find any, so its head scratching time. But if any of you guys can give me a hint I would be grateful.

 

[oakey]

Suggest you inflate it to full height then check rear bags for leaks.. If rears drop then fronts will drop too to self level

 

[Grrrrrr]

Try putting her to full extended height, switch off and then remove the delay timer from under the passenger seat (assume RHD). See which corner has dropped in the morning.

 

[J L Carr]

Try putting her to full extended height, switch off and then remove the delay timer from under the passenger seat (assume RHD). See which corner has dropped in the morning.

Been there done that, they drop both at the same time it normally take around a half hour for this to happen. I've sprayed both air bags with soapy water to find a leak but to no joy, all I can come back to is the suspension values is at fault.

 

[Grrrrrr]

Odd only the rear dropping. 1/2 hour is fast. That's all the way down? It does self-level a bit but obviously it shouldn't with the delay timer removed. Should give 35mph max message when removed.

Sometimes the exhaust gets a pinhole and then melts a hole in the airline, or so I've heard.

If it was a height sensor I would have thought it would drop the one corner and then the others as that dropped. Might be wrong as never had the issue. Or it could be the valve block but odd that both rears are dropping and not the fronts. Has it got one of those manual inflation kits with the Ts? If so I'd suggets taking that off as they tend to leak like mad.

I assume you've pushed all connections in as far as you can?

 

[oakey]

If values were wrong then suspension would stay at that height I think.
Is compressor running a lot?
I had exhaust burn a wee hole in air line took ages to trace it

 

[wammers]

Both valve block valves leaking at the same rate would be very unusual. Not impossible but unusual. Both bags leaking at the same rate again not impossible but unusual. Again both pipe connections to bags leaking at same rate not impossible but unusual. I would go for the pipes being damaged by an exhaust leak at either side where they cross over at the rear. The O/S line goes down the N/S of the car and crosses over to feed the O/S bag. The N/S line goes down the O/S of the car and across to feed the N/S bag. They cross and are clipped to each other and the body frame above and behind the fuel tank. An exhaust leak at either side could have damaged both lines. It will most certainly NOT be sensor settings.

 

[J L Carr]

Hi Wammers. I took this picture of the car, as you can see this is what happens after about an half hour to an hour after parking it up.

 

[wammers]

You will have to look for and find the leak. Did it start at wading height before the photo?

 

[Grrrrrr]

That's a FAST leak. It will kill your compressor.

Have you got some straight connectors with manual inflation valves on? Could always try manually inflating each one in turn and see if it is the line & bag or the valve block end. That would narrow it down a bit. Can you hear the exhaust blowing at all?

You're in Hemel? Not far from me.

 

[J L Carr]

Parked the car up at normal height, it even did the settling bit after I locked it. But when I came back to the car got something out and shut the door it did the usual ticking and the front end went down. As for the exhaust its all fine, no blow.

 

[wammers]

Parked the car up at normal height, it even did the settling bit after I locked it. But when I came back to the car got something out and shut the door it did the usual ticking and the front end went down. As for the exhaust its all fine, no blow.

Front is nothing like normal height. You need to find the leaks and get someone on it with diag.

 

[J L Carr]

Hi I have some schreder valves as an emergency, but as to what pressure you got to I have no idea. Just spent about an hour under the car to see if I could hear or see a leak, no joy. I know that if I fit the valves I need to disconnect the EAS unit so if you know the pressure I can try this tomorrow and see what happens. I timed how long it takes to drop around half a hour for the back end to go down, so when I come to use the car it takes about 15 mins to get it back up to ride height.

 

[tomcat59alan]

Hi I have some schreder valves as an emergency, but as to what pressure you got to I have no idea. Just spent about an hour under the car to see if I could hear or see a leak, no joy. I know that if I fit the valves I need to disconnect the EAS unit so if you know the pressure I can try this tomorrow and see what happens. I timed how long it takes to drop around half a hour for the back end to go down, so when I come to use the car it takes about 15 mins to get it back up to ride height.

15 mins is too long, you may be fecking the compressor by feeding a leak,.Start the car with a door open for 10 mins, that should recharge the storage tank. Shut the door after the 10 min and see what happens. You MUST have a leak somewhere in the system, looks like the rears are bleeding into the fronts so I would guess at the valve block. Go to the Technical Archive on the home page and check Wammer's guide.

 

[J L Carr]

I'll try that tomorrow, but at what pressure would you pump it up with the valves. Thanks.

 

[tomcat59alan]

I'll try that tomorrow, but at what pressure would you pump it up with the valves. Thanks.

I personally wouldn't, get shut as they are more chances for the system to leak. Properly maintained you shouldn't need them. IMHO

 

[Grrrrrr]

I personally wouldn't, get shut as they are more chances for the system to leak. Properly maintained you shouldn't need them. IMHO

Assume he means for testing.

assuming they're the straight connectors and not Ts then put about 30 psi each and then ease up about 10 psi at a time. Pull the delay timer relay first. As the car tilts and its weight shifts around it will come up very erratically and can bounce up quick so be ready for it once you get over 50psi.

 

[Grrrrrr]

Assume you did try testing at the valve block end too? O-rings might be damaged where the pipes go in.

 

[J L Carr]

Ye I sprayed everywhere I can think of with soapy water, even got a kit from screwfix that plumbers use to find leaks. Been out there today and gone over it again and still nothing, so still going back to the valve block. I will try the schrader valves tomorrow just to test and see if there is a leak either bags or pipe work. Lets hope I can find it.

 

[wammers]

Ye I sprayed everywhere I can think of with soapy water, even got a kit from screwfix that plumbers use to find leaks. Been out there today and gone over it again and still nothing, so still going back to the valve block. I will try the schrader valves tomorrow just to test and see if there is a leak either bags or pipe work. Lets hope I can find it.

Sometimes the drier breaking up causes a white silica gel deposit to cover the solenoid valve seals with a crust and they cannot seal properly. It is unlikely it is just effecting the two rear valves but not impossible. Isolate the valve block and inflate the arse end with your valves soap test them. If it stays up it has to be the valve block. If it drops it has to be the lines or bags. It's a case of trial and error i am afraid. Just follow logical steps.