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Discussion Starter · #1 ·
(sorry if this should be in engine forum)

Last few weeks I have developed intense paranoia over a noise of escaping air I swear I have never heard before. I hear it as I put my foot down in any gear. More noticeable if I do this at low revs but I guess that is because the engine noise is lower at that point. Coupled with this it feels like my car has lost a small amount of power.

Its an 07, unmodified.

I'm not sure that I'm not just hearing the normal noise of the turbo spooling up, and the feeling of reduced power is because I have had the car for 12 months now and I am getting used to the power?

Its boosting to just over half way on the gauge then slowly coming back down.

Thoughts?
 

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Maybe just a small boost leak mate. Have you listened under the bonnet when idle. I have an annoying air sound from my r oem recirc valve I recon i have a boosteak there so replacing it. When I veru lightly accelerate I get the noise veey annoying.

If you really want to solve it get a smoke test that way you know for sure
 

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Sounds like a boost leak from the symposer unit. you can get a blanking plug for it and take it off (does not affect performance when removed)

I had this happen to me and its an easy fix, if this is the same problem
 

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Sounds like a boost leak from the symposer unit. you can get a blanking plug for it and take it off (does not affect performance when removed)

I had this happen to me and its an easy fix, if this is the same problem
You could be right mate but it could also be anywhere. Smoke test would 100% find it. But worrhwhile to remove that ugly piping too, I would change to an silicone cooler the trottle which is without the whole for the bung & dump valve that way eliminating boost leaks altogether.
 

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+1 for symposer leak. Horrible, messy looking system anyway. Looks much better with it blanked off and removed
 

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Byron - how/where would I get a smoke test?

Chris - fair enough, I doubt I'd have resisted either


Vazz / st3x2 - is removing the symposer a DIY job? and where would I get the blanking plates?

thanks for all of the replies (except Chris
)
 

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Right, its definitely down on power. Slightly, but noticeable.

The exhaust has also stopped popping altogether - used to be able to do it on demand almost, nothing now. And a different exhaust note when i take my foot off the accelerator (which used to make it pop)

the noise under the bonnet could be something do to with the exhaust? confused now :S
 

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Discussion Starter · #12 ·
Mines been doing exactly the same, looks like new solenoid time. Thanks for posting your fix.
No problem mate. Nice to finally help someone out, rather than just being helped!

I also did a Kam reset a week before (see the how-to here: http://www.focusstoc.com/forums/topic/25485-kam-fuse-keep-alive-memory/ )

I'd also changed the spark plugs and cleaned the MAP sensor (tried to clean MAF sensor but some
before me has damaged the security torx screws so badly I can't get them out now)

The plugs and sensor cleaning made no difference. The KAM reset made a tiny improvement.

The boost solenoid cured it completely.

Apparently you can't see if the solenoid is faulty/damaged in any way, so you need to replace to see if its the problem. I took my car to Pumabuild in Brum who were kind enough to change the solenoid as they had them in stock - if it didn't fix the problem they were going to put the old one back in and not charge me.

Good luck - hope it solves your problem too. Horrible having this problem
 

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No problem mate. Nice to finally help someone out, rather than just being helped!

I also did a Kam reset a week before (see the how-to here: http://www.focusstoc.com/forums/topic/25485-kam-fuse-keep-alive-memory/ )

I'd also changed the spark plugs and cleaned the MAP sensor (tried to clean MAF sensor but some
before me has damaged the security torx screws so badly I can't get them out now)

The plugs and sensor cleaning made no difference. The KAM reset made a tiny improvement.

The boost solenoid cured it completely.

Apparently you can't see if the solenoid is faulty/damaged in any way, so you need to replace to see if its the problem. I took my car to Pumabuild in Brum who were kind enough to change the solenoid as they had them in stock - if it didn't fix the problem they were going to put the old one back in and not charge me.

Good luck - hope it solves your problem too. Horrible having this problem
It is a horrible problem. I have been convinced for ages that there was something wrong.
I too can hear a hiss at light throttle settings. I was sure it was a boost leak, but pressure tested the system and it was fine.
I have also cleaned the Maf and changed plugs.
Mine was down on power, but would still show half boost (std map)
I wonder why a dodgy solenoid would make a hiss?
If it fixes it I will be so impressed!
 

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Discussion Starter · #14 ·
I thought I was just being paranoid, like the title of my post says. Phil at Pumabuild drove my car and listened to the 'hiss' - he said it was normal for a standard ST.

My boost gauge showed it was boosting correctly as well mate, so that confirms its no real guide. Someone else on here said the gauge isn't a good metric as it just displays what the ECU thinks the car is boosting at. In actual fact the boost could be all over the place.

I can't understand the hiss being caused by the solenoid either. I've still got the noise so I'm now going to try removing the symposer unit and blanking it off as that sounds like a common cause and is easy enough to do yourself apparently.

Let me know if the new solenoid fixes it! And when its fixed, get it remapped as I did on the same day at Pumabuild. I went from no boost at low revs to grin inducing boost at 2k revs. You won't regret it
 

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I thought I was just being paranoid, like the title of my post says. Phil at Pumabuild drove my car and listened to the 'hiss' - he said it was normal for a standard ST.

My boost gauge showed it was boosting correctly as well mate, so that confirms its no real guide. Someone else on here said the gauge isn't a good metric as it just displays what the ECU thinks the car is boosting at. In actual fact the boost could be all over the place.

I can't understand the hiss being caused by the solenoid either. I've still got the noise so I'm now going to try removing the symposer unit and blanking it off as that sounds like a common cause and is easy enough to do yourself apparently.

Let me know if the new solenoid fixes it! And when its fixed, get it remapped as I did on the same day at Pumabuild. I went from no boost at low revs to grin inducing boost at 2k revs. You won't regret it
Hope your loving the map Ian, I've been running it for 7 months now and I'm not bored of it yet!! Good lads at Pumabuild and they have always gone the extra mile for me when I have needed it
 

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Discussion Starter · #16 ·
Hope your loving the map Ian, I've been running it for 7 months now and I'm not bored of it yet!! Good lads at Pumabuild and they have always gone the extra mile for me when I have needed it
I certainly do love it. Transformed the car completely. Don't know how I put up with it being standard for a whole year


A gentleman in a 911 Carrera S brought me back down to earth a little bit earlier though
 

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I thought I was just being paranoid, like the title of my post says. Phil at Pumabuild drove my car and listened to the 'hiss' - he said it was normal for a standard ST.

My boost gauge showed it was boosting correctly as well mate, so that confirms its no real guide. Someone else on here said the gauge isn't a good metric as it just displays what the ECU thinks the car is boosting at. In actual fact the boost could be all over the place.

I can't understand the hiss being caused by the solenoid either. I've still got the noise so I'm now going to try removing the symposer unit and blanking it off as that sounds like a common cause and is easy enough to do yourself apparently.

Let me know if the new solenoid fixes it! And when its fixed, get it remapped as I did on the same day at Pumabuild. I went from no boost at low revs to grin inducing boost at 2k revs. You won't regret it
Thanks for the info, I'll let you know the outcome. May be a bit of a delay as I've broken my leg and won't be driving for a bit.
Cheers
 

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Discussion Starter · #18 ·
Thanks for the info, I'll let you know the outcome. May be a bit of a delay as I've broken my leg and won't be driving for a bit.
Cheers
No probs. Sorry to hear about the leg. Will make getting back into the car even better though, hope u get well soon.
 

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I certainly do love it. Transformed the car completely. Don't know how I put up with it being standard for a whole year


A gentleman in a 911 Carrera S brought me back down to earth a little bit earlier though
Clearly you need to talk to Alan or Phil some more!!!
 
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