Vibration

  • Thread starter imported_VaulterTim
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imported_VaulterTim

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Hey guys,

I've got a nasty vibration from my engine, specifically in or around the turbo area /ubbthreads/images/graemlins/frown.gif

It is most evident on the overrun (revving slightly then letting the engine run down to idle).

It sounds like a guard or heatshield or similar and since there are a few around that area I just wondered if maybe anyone had encountered a similar problem in the past. I've already tried moving, bending and holding all the heatshields I can get to out of the way, but to no avail.

I've literally had the car in pieces as I initially thought it may be the CAT.

AndyC kindly loaned me his old CAT (with internals removed /ubbthreads/images/graemlins/smile.gif) but after installing it the sound only seems to have gotten worse... I think that whatever it is may be INSIDE there somewhere and the CAT was acting as a muffler... Removing it seems to have made the sound echo or something!

I then thought it may be the turbo because I put my finger inside the turbine housing to have a feel around after I'd removed the CAT just to see if there was any play in the shaft... there was none at all but I could feel something moving around in there and making a small metallic knocking noise... wastegate maybe? I don't know.

Any suggestions/experiences/stories would be great... I'll be installing the big turbo soon anyway so it's not a major issue, it's just driving me crazy! /ubbthreads/images/graemlins/mad.gif

Cheers

Tim

P.S. Got a lovely sound, if not a little Max Powerish!, from my DV now that I've removed the airbox and replaced it with the crappy cone filter that came in my kit! (I couldn't be bothered putting the airbox back in after dismantling the other lot because it was late and too much of a fiddle in the fading light and the cone was just sitting there begging to be used! I'll probably chuck it when I do the big turbo anyway so I thought I may as well get SOME use out of it!). There's lots of induction roar now and the DV gives that Pttsssssh! noise when it goes off /ubbthreads/images/graemlins/ooo.gif
 
[ QUOTE ]
Hey guys,

I've got a nasty vibration from my engine, specifically in or around the turbo area /ubbthreads/images/graemlins/frown.gif

It is most evident on the overrun (revving slightly then letting the engine run down to idle).

It sounds like a guard or heatshield or similar and since there are a few around that area I just wondered if maybe anyone had encountered a similar problem in the past. I've already tried moving, bending and holding all the heatshields I can get to out of the way, but to no avail.

I've literally had the car in pieces as I initially thought it may be the CAT.

AndyC kindly loaned me his old CAT (with internals removed /ubbthreads/images/graemlins/smile.gif) but after installing it the sound only seems to have gotten worse... I think that whatever it is may be INSIDE there somewhere and the CAT was acting as a muffler... Removing it seems to have made the sound echo or something!

I then thought it may be the turbo because I put my finger inside the turbine housing to have a feel around after I'd removed the CAT just to see if there was any play in the shaft... there was none at all but I could feel something moving around in there and making a small metallic knocking noise... wastegate maybe? I don't know.

Any suggestions/experiences/stories would be great... I'll be installing the big turbo soon anyway so it's not a major issue, it's just driving me crazy! /ubbthreads/images/graemlins/mad.gif

Cheers

Tim

P.S. Got a lovely sound, if not a little Max Powerish!, from my DV now that I've removed the airbox and replaced it with the crappy cone filter that came in my kit! (I couldn't be bothered putting the airbox back in after dismantling the other lot because it was late and too much of a fiddle in the fading light and the cone was just sitting there begging to be used! I'll probably chuck it when I do the big turbo anyway so I thought I may as well get SOME use out of it!). There's lots of induction roar now and the DV gives that Pttsssssh! noise when it goes off /ubbthreads/images/graemlins/ooo.gif

[/ QUOTE ]

Tim,

JayB also has the same problem on his A4 1.8T... We cant figure it out either! completely stumped by it infact.... The noise is untraceable. V V hard to pin point. The wastegate is a n nteresting theory though... May disconnect the vacuum from it and try it...see if this has any effect.

Rich
 
I'll do the same... and also keep poking around... but there's not much left to poke without ripping the car apart!

I hate losing at the best of times and I won't be beaten on this! /ubbthreads/images/graemlins/burningmad.gif

Keep me informed mate.

Cheers

Tim

P.S. It hasn't always been there... only recently, maybe the last two months or so, and it's getting worse /ubbthreads/images/graemlins/frown.gif
 
Only vibrating sound I had was from the Windscreen wipers but this was soon sorted by bending them back into shape.

Fit the GT - go on you know you want to.... /ubbthreads/images/graemlins/smile.gif


Greg
 
I've just finished 'poking' again and I'm sure I've found the problem...

My original suspicions were correct, it is the wastegate.

Rich...

If you use a long bar of some kind (I used a long ratchet extension) and place it in the gap between the wastegate actuator arm and the manifold, you can place a small amount of pressure on the arm by levering it slightly.

I think you'll find that the vibration stops. Mine did.

The only way of finding out exactly what is wrong with it is to dismantle the turbo. Although if you just wanted to have a look in there, disconnect the CAT and use a mirror to look inside...

Hope this helps, keep me posted mate.

Cheers

Tim
 
I have exactly this problem. Just got back from a long weekend in Cornwall, during which It's been getting right on my tits. I had the car serviced last week at a specialist, and asked them to have a look. They said they thought it was an exhaust heat sheild rattling, but couldn't pinpoint it. I would be very interested to hear any solutions that may be found. I also have a 99 1.8T.
 
I and a few others thought it was a heatshield to start with but after poking around and experimenting a little (as above) I found out it wasn't unfortunately... /ubbthreads/images/graemlins/frown.gif
 
This problem has got me a bit stumped. I have a metallic rattle that you can hear mainly when changing gear. If i rev the engine while standing the rattle starts as the revs begin to fall, and stops as it gets back to idle.

Tim, did you cure this on your car or do you still have the rattle? If you did cure it what was needed?

I am going to my parents at the weekend so will get the car up on my dads ramps to try and confirm the source of my rattle. If it's is, as Tim suspects, the turbo wastegate what would be required? Is this a servicable part? or would I need a new turbo? If I continue running with this rattle could further damage be done? and is performance being affected? If I need to replace the turbo whats the damage to the wallet likely to be? I've seen replacement turbos for under £400, but I imagine fitting is a bit of a job?

Any advice that could be offered would be gratefully received, as I'm unsure what to do and getting thoroughly p!$$ed off with this rattle.

Cheers

Andy
 
Andy,

As previously said, this is definately your wastegate.

Unfortunately there is not a great deal you can do about it except changing the turbo and yes, I too get annoyed as hell with it, makes the car sound knackered... /ubbthreads/images/graemlins/frown.gif

I haven't cured it yet, doubt I will. I'm not even sure what the exact cause of the noise is until I take the turbo off, just that the wastegate rattles like crazy under the circumstances you mention above. Although, it won't be long until I remove the turbo (few weeks) so watch this space and I shall let you know what I find.

Even if there were a way to fix the wastegate itself, that would obviously involve removing the turbo since the wastegate is inside it.

It hasn't affected the performance of my car oddly... and the noise seems pretty constant now. Although I can only imagine, since the noise wasn't there previously, that the presence of it suggests some sort of degradation somewhere down the line and if this is true, as with all things mechanical, it will only get worse.

Maybe source a replacement turbo if you like, or you could just live with it and see how far things go. Mines been like it now for quite some time, maybe 3000miles or so.

Up to you dude...

Regards

Tim
 
JayB's A4 does this and its very annoying, and does sound knackered! It could be the wategate, or just the actuator. I've got my old K03 sat in my garage from my A3, so i may swap the actuator on the A4 and see if it stops, because my K03 is still in perfect condition!

RIch
 
Rich

If you do this I'd be very interested to know the results!

Cheers

Andy
 
[ QUOTE ]
JayB's A4 does this and its very annoying, and does sound knackered! It could be the wategate, or just the actuator. I've got my old K03 sat in my garage from my A3, so i may swap the actuator on the A4 and see if it stops, because my K03 is still in perfect condition!

RIch

[/ QUOTE ]

Yes Rich, had a previous discussion with Jay re. this problem... you can hear mine at idle too. As you say, it could be the actuator or the wastegate itself but at present it's difficult to tell without pulling it off there. I'm erring toward the wastegate at present since the noise seems to be coming from inside the turbine housing.

We'll see...

Tim
 
[ QUOTE ]
[ QUOTE ]
JayB's A4 does this and its very annoying, and does sound knackered! It could be the wategate, or just the actuator. I've got my old K03 sat in my garage from my A3, so i may swap the actuator on the A4 and see if it stops, because my K03 is still in perfect condition!

RIch

[/ QUOTE ]

Yes Rich, had a previous discussion with Jay re. this problem... you can hear mine at idle too. As you say, it could be the actuator or the wastegate itself but at present it's difficult to tell without pulling it off there. I'm erring toward the wastegate at present since the noise seems to be coming from inside the turbine housing.

We'll see...

Tim

[/ QUOTE ]

Tim,

If the actuator had gone, then its the wastegate that would be causing the noiss. The wastegate in the turbo is just that... a gat on an arm. The actuator is the force on this and keeps it closed. I will see what we can do and let you guys know.

RIch
 
[ QUOTE ]
[ QUOTE ]
[ QUOTE ]
JayB's A4 does this and its very annoying, and does sound knackered! It could be the wategate, or just the actuator. I've got my old K03 sat in my garage from my A3, so i may swap the actuator on the A4 and see if it stops, because my K03 is still in perfect condition!

RIch

[/ QUOTE ]

Yes Rich, had a previous discussion with Jay re. this problem... you can hear mine at idle too. As you say, it could be the actuator or the wastegate itself but at present it's difficult to tell without pulling it off there. I'm erring toward the wastegate at present since the noise seems to be coming from inside the turbine housing.

We'll see...

Tim

[/ QUOTE ]

Tim,

If the actuator had gone, then its the wastegate that would be causing the noiss. The wastegate in the turbo is just that... a gat on an arm. The actuator is the force on this and keeps it closed. I will see what we can do and let you guys know.

RIch

[/ QUOTE ]

Cheers for the lesson Rich /ubbthreads/images/graemlins/lol.gif

I must admit though, I've always thought the noise sounds like the wastegate slapping on it's seat... kinda tinny.

T
 
[ QUOTE ]
[ QUOTE ]
[ QUOTE ]
[ QUOTE ]
JayB's A4 does this and its very annoying, and does sound knackered! It could be the wategate, or just the actuator. I've got my old K03 sat in my garage from my A3, so i may swap the actuator on the A4 and see if it stops, because my K03 is still in perfect condition!

RIch

[/ QUOTE ]

Yes Rich, had a previous discussion with Jay re. this problem... you can hear mine at idle too. As you say, it could be the actuator or the wastegate itself but at present it's difficult to tell without pulling it off there. I'm erring toward the wastegate at present since the noise seems to be coming from inside the turbine housing.

We'll see...

Tim

[/ QUOTE ]

Tim,

If the actuator had gone, then its the wastegate that would be causing the noiss. The wastegate in the turbo is just that... a gat on an arm. The actuator is the force on this and keeps it closed. I will see what we can do and let you guys know.

RIch

[/ QUOTE ]

Cheers for the lesson Rich /ubbthreads/images/graemlins/lol.gif

I must admit though, I've always thought the noise sounds like the wastegate slapping on it's seat... kinda tinny.

T

[/ QUOTE ]

Yep, this may well be the case, but i think the cause would be the actuator, not the wastegate itself.

Rich
 
Rich

If it does turn out that it is the actuator that is letting the wastegate rattle, is this a part that can be replaced easily? Would the turbo still require removal to fit it? And would it be easy to get hold of an actuator?

Cheers

Andy
 
[ QUOTE ]
Rich

If it does turn out that it is the actuator that is letting the wastegate rattle, is this a part that can be replaced easily? Would the turbo still require removal to fit it? And would it be easy to get hold of an actuator?

Cheers

Andy

[/ QUOTE ]

Andy,

I think it may JUST be possible to do it with the turbo in place, but even if not, its not major job. You cannot buy the actuator separately unfortunately so would need to find one from a scrappy

RIch
 
Rich

Thanks very much for this info. If it does turn out to just be the actuator I think I may owe you a pint!

Didn't have time to have proper look at the weekend, but will hopefull get the chance to have a good poke around this weekend. Could you possibly give me a pointer to where the actuator is located? I've had a look but not been able to spot it. Is it easier to access with the airbox and the heatshield below it removed? Whats the best way to determine if it is the actuator?

Any pointers would be really appreciated!
 
Am I correct in thinking that the actuator is the small drum with the bar coming out of the bottom, that then connects to the small swing arm, which I presume is connected to the wastegate?

see below
A&m%20am04%204.jpg
 
That's it.

Do as you say and you'll see it.

Wastegate is the round thing in the big hole on the right!

T
 
[ QUOTE ]
That's it.

Do as you say and you'll see it.

Wastegate is the round thing in the big hole on the right!

T

[/ QUOTE ]

Yep. Took a look at it last night and my K03 actuator wont mount on the A4 K03 unfortunately, so were going to whip the turbo off and take a look at it. If its the actual wastegate itself then its new turbo time, if its the actuator, then its a cheap job.

Rich
 
Rich

I'll wait to hear your results!!

How does the actuator actually work?

Andy
 
[ QUOTE ]
Rich

I'll wait to hear your results!!

How does the actuator actually work?

Andy

[/ QUOTE ]

Vacuum. The N75 is a 'gateway' controlled by the ECU which tells it to open at certain boost pressures. When the N75 opens, a vacuum pulls in the actuator rod which is connected to the wastegate, therefore opening the gate which allows boost to be managed. the n75 opens and closes very radidly as regualte boost (not too much, not too little)

Rich
 
Rich,

As far as I can tell from poking around with various turbos over the years, the only thing that can actually break on a wastegate seems to be the weld that holds the actuator arm to the pivot on the wastegate itself.

I wouldn't imagine there to be anywhere near enough pressure or force acting upon the wastegate (which is made of steel don't forget!) to break it, unless it has somehow managed to crack which to be honest would be very unlikely. Since there seems to be at least a few of these cases I am inclined to guess at it being the week link at the moment, that obviously being the actuator. So I think you're right with regards that.

Let us know when you pull Jays tubby off /ubbthreads/images/graemlins/grin.gif

Cheers

Tim
 
I just got my car back from the garage. As you know, i had this rattle noise when you put your foot down and then lift off. The garage took it back and initially said it wasnt the turbo that dneeded replacing but there was a pin in the arm ( i presume of the actuator) that was rattling. To stop it rattling, they needed to crimp the part around the pin just enough to stop it rattling, but not enough to stop it moving / rotating. The turbo still has to come off to do this. Any who, the next day, i get a call saying i dont know what theyve done but you needs a new turbo. Ah, so at last you agree with me! I dont know the exact details of what was wrong, but they have fitted a recon turbo at a small charge to me ( they would only fit a 2nd hand one under warranty, the tight peeps) and now i got it back and all is quiet. It even makes a flutter noise when you change up on hard acceleration!

If i feel like it i will call the mechanic and try to write down what he says, so i can let you know. I have had enough of phoning these people. They even ran it out of fuel for me before giving it back. I mean it stopped 1/2 mile away from the garage. They could have chucked a fivers in you know what i mean?

Regards

Nige
 
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