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Discussion Starter · #1 ·
Only happened about 2-3 months ago, car has been fine for nearly 2yrs in my ownership.

After sitting overnight say, i start the car and it idles slightly higher as it always has (told its to warm up?) and then it settles down to a usual 800rpm-ish. Now, it does that, but is accompanied by a really rough metallic sound, almost as if the exhaust is blowing really really bad.

Strangely, if you give it about 2 mins, theres a loud dispersion of air/pressure from the left/front of the engine area, the idle settles, and the car is silent...???

Its not a massive problem obviously, slightly irritating as everyones pointing it out, and with the car only having 4 weeks left of warranty im worried that what is there might become worse.

Its one of the tricky ones to get them to fix as well with it only happening at cold! Any ideas??

ta
 

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Definately the secondary air pump. Might be worth sorting the temperature sensor at the same time.

It does get worse, it get's embarasing.

What happens is with all the pressure, the secondary air pump starts to split. So the noise your hearing is the air escaping from it, so I'm led to believe. The whooshing noise at the end (it's actually around 90 seconds) is the secondary air pump winding down.

You will find it doesnt do it if you start the car within about 4 hours of each startup. Leave it anything between 4-7 hours and it will do the noise again.

I got my secondary air pump off the bay for ?80. But I was lucky. It was also a Seat air pump, modified not to fail. I.e. extra bolts were used to keep it clamped shut, you could tell the difference between the old one and the new one.

Another failing part by the OEM group and another part they don't bother just modifying to put right.

A new one, off the shelf will cost around ?370. Fitting cost me ?45.

Yours chris will literally be coming apart and every time you use it, will blow itself apart even more. It will get to the stage where you can't drive the car while it's doing it as you'll either be like a rocking horse trying to get the acceleration smooth or you'll just stall as not enough air is getting into the system.

I used to just sit there in the car park for 90 secs making a huge noise and getting embarrased.

Also, the secondary air pump is used about 5 mins after starting and sometimes when stopping at lights etc. So be prepared. If you hear that noise, you know to be careful with the throttle, it really is very hard to drive if it get's worse. So one minute your driving fine, the next min, your all over the place.
 

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Discussion Starter · #5 ·
Bugger!

Sounds definately like thats what it is then.... ill get it booked in asap and tell them to keep it overnight if need be so it can be diagnosed properly, gotta get it sorted before the warranty expires!! I wonder whether to just tell them i suspect its the secondary air pump, and just say i had it on my old GTI so they cant try and fob me off?

Would it be having an adverse effect on performance? I know the airs muggy and the 1.8T always struggles to a certain extent, but it doesnt feel half as lively as it used to...

Is the pump visible at all from the engine bay EJO? Or is it a hidden little sod.

Cheers for the help.
 

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its either the ECU relay, lamba sensor (which I doubt) or its the MAF. Try to borrow a MAF from someone to try it.

get vagcom and see if there is any fault codes appearing.
 

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its either the ECU relay, lamba sensor (which I doubt) or its the MAF. Try to borrow a MAF from someone to try it.

get vagcom and see if there is any fault codes appearing.
It's non of those and VAG COM won't show a code. It didnt with mine anyway.

It's actually quite a large part. It's a black unit underneath the turbo, say a foot underneath it. You can't see it just by looking.

Looks like this:
Posted Image


This is a BMW onem but looks exactly the same as what I got.
Posted Image


Now, on the drawing picture, those round bits at the top of the unit, on the big circular bits are the joints from what I could see. They are what keeps it together. There are no screws, I presume it's molded.

On the new one that I got, aswell as being molded, they had put bolt's through there also.

So on that picture, you can see what's happening to yours, it's literally splitting at the top and that big round bit at the top is being forced away from the pump.

Now, I say all this as if I know what I'm on about! I'm just passing on what the mechanic told me when he took my old one and explained it to me! (this was an independant garage)

I took mine to where I bought it and they sent it to VW. VW said they couldnt hear anything wrong and it's just wear and tear. Yer right. So had a massive argument with them. They kept saying they couldn't head anything wrong because they kept starting it, knowing that it wouldnt do it unless they left it for so long.

Then when I had a bigger go at them, telling them I'm not stupid and they can't fob me off with their tricks, they said that there are no codes coming up in the engine apart from my door lock thingy that was also wrong, so they don't know what part to replace, but they can do some diagnostic tests for ?800 + VAT.

Nearly punched them and gave in, nothing I could do. Went about it my own way. It wasn't covered under the warranty anyway as it turns out. So your may not be either. Just like the clutch isnt etc.

Once the pump was replaced, the noise dissapeared, but it did throw off my temp sensor, so was still idling high. Replaced that and car was soooooo nice to start!

The only performance issues I had was when the pump was being used. I.e. on startup and when I stopped etc. Then performance was dodgy and like I say, felt like a nodding dog until the unit had done its bit, then everything was smooth again.

Got a sound clip of mine and how bad it got which I used for VW if you want it. This is what they couldnt hear.....[:p]
http://www.dartmedical.co.uk/car/Recording.wav

If it's even slighlty as noisey as that, then you will have the same problem, and thats how bad it get's! [:D] Listen right till the end when the pump switches off! [:O]
 

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Discussion Starter · #8 ·
Oh bahoolicks...... thats exactly what it sounds like now!!

Right, its going in this week, and they WILL be fixing it under warranty, cars only got 26k on it for goodness sake!
 

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Oh bahoolicks...... thats exactly what it sounds like now!!

Right, its going in this week, and they WILL be fixing it under warranty, cars only got 26k on it for goodness sake!
Yes, but VW won't be able to hear what the problem is! [:D]

They thought that was normal! Honest! That was VW in Exeter. I did a write up about it ages ago, can't even remember the title though, but a search on secondary pump or whatever should bring up some related results.
 

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Discussion Starter · #10 ·
Well, its booked in for next Tuesday. Agreed with them to drop the car off end of play on Monday so the issue will be replicated on tuesday morning. I also told him that i had an identical problem on my MKIV Golf and it turned out to be the secondary air pump.... i didn't, but at least they know what i suspect [;)]

Fingers crossed then - good thing is its in for its 1st MOT at the same time, and from what ive read both on here and other forums, its that without the air pump operating properly the car is likely to fail on emissions - good if it does, they cant get outta it then.
 

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I have a MK IV Golf and had exactly the same problem with my
secondary air pump, as mine is no longer under warranty I managed to fix
the problem myself.

The reason for the loud hissing noise was as mentioned before the unit
leaking air, also as the unit loosened the rotating plates inside were rubbing
against the plastic housing, the aluminium rivets that are used to clamp the
unit together are not really up to the job as they corroded and came loose, there
are 6 rivets around the outside of the unit, all I did was remove the pump along with its retaining bracket, drilled out the old rivets with a
4mm drill bit and bolted the unit together with some spring washers and M4
bolts in place of the old rivets, sounds just like new now.
 

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I have a MK IV Golf and had exactly the same problem with my secondary air pump, as mine is no longer under warranty I managed to fix the problem myself.
The reason for the loud hissing noise was as mentioned before the unit leaking air, also as the unit loosened the rotating plates inside were rubbing against the plastic housing, the aluminium rivets that are used to clamp the unit together are not really up to the job as they corroded and came loose, there are 6 rivets around the outside of the unit, all I did was remove the pump along with its retaining bracket, drilled out the old rivets with a 4mm drill bit and bolted the unit together with some spring washers and M4 bolts in place of the old rivets, sounds just like new now.
Thats a bit of genius! I wouldn't even know how to take mine off, but wish I had kept my old pump now!
 

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No didn't think to take any pics, It was a pretty simple job maybe a little awkward in getting the pump out.

To get access to the pump I had to jack the car up a little to get at it from
underneath, I had to remove a plastic cover which spreads across the underneath
of the front end of the engine bay, I used a T20 size star key to remove the 4
screws holding the cover.

Once the plastic cover was removed it was just a case of removing the two air
hoses from the pump, the power connector and undoing the bracket that holds the
pump, the bracket needed a 8mm Alan key, there are 3 bolts on the
bracket, the bottom 2 bolts can be undone from underneath the car, the top bolt
can be undone blindly from the top, once the brackets undone you can remove the
pump and bracket as one from underneath.

<o:p> </o:p>Once the pump is out the rivets should be obvious to spot, I
would recommend using spring washers or nyloc nuts to fix the pump together as
just a nut and bolt could come loose with the vibrations encountered.

<o:p> </o:p>

Hope that helps.
 

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Discussion Starter · #15 ·
Grrrrrrrrr.

I knew this wouldn't be straight forward. It's passed its MOT but apparantly the noise is the centre section of exhaust blowing..... at 26k!?!?!! I asked how its going away after 2-3 mins and then getting a loud release of air, and apparantly thats cos its heated up and expanded.

So im going to get the exhaust checked and if theirs nothing wrong im going back for an argument. Methinks with 2 weeks of warranty left they are trying to kill time.

I know warranty doesnt cover exhausts but jesus, 26k, not even half the mileage allowed under warranty conditions, your having a laugh!
 

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Sorry but LMAO at the exhaust theory!

VW denied all knowledge of mine also, just like I said. They were very very happy to say 'yes, thats the secondary air pump' on the phone when I was enquiring about prices though.
 

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Discussion Starter · #17 ·
Success!

After being mucked around and lied to by the first garage, today i tried another Seat garage. Booked in again, told them what i thought the problem was, and left in a lovely mincing blue micra courtesy car.

Fully expected a cock n bull story again, but to my amazement, got a phonecall to say the problem has been identified as the secondary air motor, which is on back order (i wonder why!!) but will be fitted under warranty next week when it arrives!

So hats off to North East Garages Seat! [:D]
 

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just sorted mine ....

very simple when you get the thing out quite easy to get to when jacked up and bottom splash guard is of

the only hassle i had is the bracket that holds it needs moved to the side and one of the bolts that hold the bracket is half way up the engine and is a mare to get to but this only needs loosend so you can swing the bracket aside a bit .



as you can see the rivits on the outer edge are the problem one of mine was missing and the others fell out

i used bolts and nuts and nylock ..... good as new

cheers for all your help guys

stuarty
 

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Hi Chris,

Can you record yours as EJO's link abive does not work. As mine has the same engine as yours and is also a Seat, I guess there is a chance mine will go too.

Cheers,

Al

PS - Are you going to get yours mapped now the warranty has finished?
 
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