TD5 Rear Air suspension problem

[lyndon]

I had a problem with the air suspension when I bought my 1999 TD5 ES. Occasionally she would sit down on the bump stops on the nearside rear. That was about a year ago. She went back to the dealer I bought her from and they replaced both the rear airbags. Not had a days trouble since until now. Suddenly she is sitting on her bump stops again on the rear nearside. But this time its everytime I park her up. The strange thing is I have just had a good look for a leak with soapy water and for 5 minutes nothing not a sauage and she stayed up fine. Then all of a sudden I could hear air escaping so soaked the rear nearside air bag with soapy water and air is escaping from around the bottom of the airbag where the cylinder enters the bag. Now I can understand there being a leak these things happen but why the delay ?.  If it started to leak straight away I would say no problem seals gone, but it holds air for 5 minutes then leaks. Anyone got any suggestions ?.

[lyndon]

Anyone?.

[Range Rover Blues]

I don't know about the delay unless it's self-levelling when it's parked like the RRC, but the leak around the bottom of thr air bag could just be much that's worked it's way in there.  Drop the alxe away by jacking under the chassi and give it a gentle hosing to removed any debris (don't wash it further in) or clean with a rag.

[lyndon]

Thanks mate. It still self levels when I switch off and lock up. Small escape of air can be heard and it drops an inch or so. Its always done this. Tonight it stayed up for a good ten minutes then just dropped. You can hear the air escape. I am not sure where the air comes out when the suspension is lowered after being raised but could it be from the botom of the air bag and therefore something is wrong with the sensor or valve?. Doesn't seem likely, but I was thinking it might be a loose clip holding the bag on at the bottom, but then surely if thats the case there would be no delay. Its as if the bag holds the air and then for some reason allows it to escape like flicking a switch if you know what I mean.

Might have to speak to Landrover dealer tomorrow. Its booked in to be looked at on Wednesday by a local small independant who specialised in Landrovers and has all the computer kit to check the electronic stuff out. Don't want to be stung for a new airbag if I don't need one. I will try out what you say mate see if it works.

Lyndon

[Range Rover Blues]

It's possible that there is muck trapped in one of the vale seals within the control unit.  Unlike the RRC your DII has no reservoir for compressed air, so the valve block is a much simpler item but still relies on O rings for seals in the valves.  It could be one of these is split or contaminated, also it could be a faulty rife height sensor, but if it were I'd expect you wouldn't be able to engage high profile.

[lyndon]

I take it its possible that once the compressor is off when parked pressure slowly builds up in the airbag owing to the weight of the vehicle on it until it reaches a point where the faulty seal just gives out. Sounds feasible.

[Range Rover Blues]

Pressure in the airbag will always be there, but without the ignition there is no compressor to keep the bag inflated which is why they go down slowly.

Yours goes down fast though, so i wonder if there is a problem with one of the height sensors or something.  If I get time I'll have a look at the help files on Rovacom for some info.

Meanwhile, di you have the factory alarm or an aftermarket one?

[lyndon]

The vehicle hasn't been modified in any way so I am guessing factory fitted alarm. Just spoek to two Landrover dealers. One wouldn't help unless I booked it in, even though its quite easy to explain whats happening. Second says it sounds like there might be corrosion on the base plate causing the seal to break. Says its about £100 for the part and one hours labour to fit plus vat so just shy of £200.

Its doesn't go down that fast. The strange thing which nobody has been able to explain is why it take ten minutes before it starts to leak. Once it starts going down it takes about 5 minutes or so to go down fully. The airbag is sound no holes, hense why the dealer thinks its the base plate. I also think personnally it might be the clip holding the airbag on at the bottom may have come loose. Is that feasble ?.

[Range Rover Blues]

The clip doen't go intot he air, but a new bag is less than £75 nowadays IIRC and yes about an hour to fit yourself ;)  Not convinced by that story though :-k

Here's a thought.  Park up and disconnet the ECU somehow, pull a fuse or whatever it takes and see if it still goes down.  Either the air system leaks, possibly as you thought once some of the pressure goes a seal somewhere opens up, or alternativley the control system (electronics) is opening the valves.

Does the system still work as nomal? going up and down with the alarm fob etc?

[lyndon]

I don't have the alarm fob device for adjusting the level. I am sure it is an optional extra I havn't bothered with. If I am right you can make the vehicle sit right down on the bumps for loading and unloading with that. It works fine though with the dash board switch. Goes up the extra few inches and comes down again great. Its only with the ignition off you notice anything different. The air is definatley coming for the bottom of the NS airbag. It can be quite easily seen when wet.

[Range Rover Blues]

Then strip that airbag off and give it a good clean around the seat, if it's leaking and can't be fixed fit a new one, you can DIY, as you say it only clips in :)

[mike142sl]

I don't have the alarm fob device for adjusting the level. I am sure it is an optional extra

It is an optional extra. I got one for mine and was a bit disappointed as it's quite slow and quicker just to jack the jockey wheel up on the caravan or trailer - EXCEPT when I was on camp in a boggy field and the twin axle scout trailer jockey wheel sank into the grass, it allowed me to lower the tow ball to the trailer instead - so it has proved its worth but ordinarily I would not recommend them.

[lyndon]

Problem sorted. New airbag fitted sound as a pound now. Still can't really explain why it only leaked after a while. But there you go.

[mud-club-matty]

get them at work all the time..  did you replace both air bags?

[lyndon]

No mate. The offside is sound. This is the second one on the nearside in 10,000 miles though. Bit worrying.

[Range Rover Blues]

Problem sorted. New airbag fitted sound as a pound now. Still can't really explain why it only leaked after a while. But there you go.

Does the air suspension self level? it's possible the leaky side was going down and proped up by the 'good' side untill the system self-leveled.  That's sortof what RRC EAS will do if a bag leaks but it's not as obvious as all 4 wheels are involved.

[Range Rover Blues]

No mate. The offside is sound. This is the second one on the nearside in 10,000 miles though. Bit worrying.

Nearside drives throgh more debris, plus the replacement might not have been OEM spec.