CGT suspension

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Discussion

Excited owner

Original Poster:

86 posts

33 months

Thursday 10th March 2022
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Hello,

On my CGT Y 2004, I have noticed when starting up the front left side there is noise like a pump.

I think it may be to do with the air suspension, but have not noticed the left hand side wheel arch lower than the rest if the car.

I have seen a Front Left Air Strut Suspension Spring Bag on ebay will this do the trick and also how big a j9b is it to fit?

Thanks in advance

sandysinclair

304 posts

213 months

Saturday 12th March 2022
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I'd echo the above , the pump is located under a plastic cover underneath the boot between the exhausts and it should only really run at the very beginning just after start up , to give the system a small boost for 3- 4 seconds , if it's running constantly when the car is switched on ,and you have a drooped front suspension then you have blown seals at the top of the suspension strut, they gradually degrade over time and they cannot be repaired , I had to this identical issue on my GTC I just looked at my bill and my garage took it out and replaced it in 1.5 hours. The total bill for a reconditioned part through flying spares was £980+ vat for the reconditioned strut and £130+ vat for the labour . There is no real shortcut here as the struts are usually year and chassis number specific and buying something on eBay that is a an unreconditioned and unwarrantied part, I will 100% guarantee you , it will fail within a couple of years.

Excited owner

Original Poster:

86 posts

33 months

Saturday 12th March 2022
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ColourRestorer said:
Whilst I’m sure the post above (by GT3ZZZ, but now deleted) is well meant, it is totally incorrect: on an early CGT there is no high pressure fuel pump anywhere near the front of the car.

What there is, at the rear of the near side wheel arch is a vacuum pump and reservoir that provides vacuum for a number of applications including turbo boost control, and exhaust flap opening.

The pump should run at start up for a few seconds until the reservoir is empty. If it runs continuously, or every time that you press the brake pedal, then you’ve got the usual VW problem of split vacuum pipes.

Rather than vacuum, the air suspension relies on positive pressure from a pump and reservoir located beneath the spare wheel, and co-located with a valve block which directs pressure, via small diameter plastic pipes, to the appropriate strut as required.

If a corner sags only whilst parked, then it could be any of these things at fault, but if you want to isolate the fault then you could try simply swapping pipes at the valve block.

If it never achieves the correct height then you may need to recalibrate the ride height settings using VAGCOM/ODIS/VCDS.

Swapping a strut is an afternoon’s work, but beware tightening the pivot bolts without the suspension correctly loaded.

Personally I would not attempt to disassemble a strut - I would only ever replace the whole thing.

You’ll need a ZXN bit to undo the top mount bolts, and patience to remove the 'b!*&%$d pinch bolt from hell' which holds to the two upper arms to the upright. VW put them in dry, and they always seize. My trick is to snap the head off then use the original retaining nut with an increasing number of greased packing washers to gradually draw the stump of the bolt out.

If you haven't yet bought the workshop manual then I would recommend splashing out £30 here: https://www.flyingspares.com/parts-workshop-manual...


Edited by ColourRestorer on Saturday 12th March 14:51
Thank you very much.

My apologies I went on to assume so.ething there, the pump sounds is coming fro the front passenger side, I now think it is not the strut as all wheels are aligned correctly and there is no sag, so maybe need to get the van com for code.

I have noticed the pump or whirring sound as I call happens only inthe morning upon startup and again only when the car is a bit cold ot not been driving for a few hours

Excited owner

Original Poster:

86 posts

33 months

Saturday 12th March 2022
quotequote all
Thanks,

I will star with the vag com, just worried if it vacuum related that's all.


Fiammetta

404 posts

94 months

Saturday 12th March 2022
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As others have said the vac pump ( inside the front wheel well ) runs for up to 40 secs when cold .Which is what you are experiencing.Touching the brake when cold also initiates it .Once the car has ran a bit warmed up and thus created its own vac you never really hear it again .
If there was a significant leak in a vac line the CEL would illuminate before the pump burnt out .
Yours sounds perfectly normal .

Air strut .
As said the pump etc is under the spare wheel well under the boot .
Crucially when you lock the car it attempts to self level .So if it’s locked side ways on a slope it might be just that front nearside lowering ( or the others raising ) to level ? If so it appears the front nearside has dropped .
Again massive air strut failures show on the dash screen in red “ suspension error see workshop “ or words to that effect .

For piece of mind you could try cycling through the ride height , the Jack mode and the softness settings .If there is a problem the car will tell you .
Engine running doors closed and after Jack mode just run a few hundred yards to unlock it .

Excited owner

Original Poster:

86 posts

33 months

Saturday 12th March 2022
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Brilliant, thank you very much, that explains it, as it has been cold and I have only had the car about 8 weeks.

Glad I asked you (and evryone) very helpful, I was getting worried.

Used jack mode a few times but will check what you suggested.

One thing I'm curious and will check manual, what does the suspension high setting used for? (not the other onerone that has 4 setting i.e. comfort, sport settings).

Fiammetta

404 posts

94 months

Sunday 13th March 2022
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High is just increased ground clearance .It’s has speed boundaries though.Once you exceed certain speeds it automatically lowers anyhow .

Excited owner

Original Poster:

86 posts

33 months

Monday 14th March 2022
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Thanks, so will it help with humps in the road or anything else, is it safe to drive locally?