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Loud 'ticking' sound when boost kicks in

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  #1  
Old 02-05-2011 | 08:53 PM
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Default Loud 'ticking' sound when boost kicks in

Now that I have my ignition problem taken care of, I'm having fun testing out the turbo now. One thing that worries me a little is an occasional ticking noise that I hear when beginning to boost. It seems to happen more when I'm heavy on the throttle in low rpm's and once I reach about 2700 rpm's the boost hits and that sound happens. While in boost range and I floor it, I don't really notice it. Could this be a sign from surging? My n75 is going bad so I'm thinking that might be a cause. Or hopefully my turbo isn't starting to self-destruct, that's all I need.
 

Last edited by A4 2000; 02-09-2011 at 04:16 AM.
  #2  
Old 02-05-2011 | 10:10 PM
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What makes you think that your N75 is going bad?

Could be the cam chain tensioner.
 
  #3  
Old 02-06-2011 | 02:56 AM
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Originally Posted by lm0812
What makes you think that your N75 is going bad?

Could be the cam chain tensioner.
Well, I don't have a boost gauge, but when at half-throttle I feel boost go on and off and can hear the turbo whine go on and off accordingly. If it were the cct, wouldn't I hear a problem at idle or when not in boost range too? The ticking sound isn't like an engine tapping sound and is not consecutive or in accordance to rpm. It's kind of hard to explain, it's random and more like an electrical arc sound like a snap.
 

Last edited by A4 2000; 02-06-2011 at 03:00 AM.
  #4  
Old 02-06-2011 | 03:09 AM
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Originally Posted by A4 2000
Well, I don't have a boost gauge, but when at half-throttle I feel boost go on and off and can hear the turbo whine go on and off accordingly. If it were the cct, wouldn't I hear a problem at idle or when not in boost range too? The ticking sound isn't like an engine tapping sound and is not consecutive or in accordance to rpm. It's kind of hard to explain, it's random and more like an electrical arc sound like a snap.
Get a boost gauge!

You could try disconnecting the N75, it should put you into limp mode at 5psi. Give that a whirl and see if the problem persists.
 
  #5  
Old 02-06-2011 | 03:13 AM
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mine does that to but only when i start the car and after if warms up it goes away but the sound is hard to explain almost lie if you have a fish tank and you unplug the oxygen hose from the pump but 100x that noise i guess a arching sound is correct
 
  #6  
Old 02-06-2011 | 03:21 AM
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Originally Posted by lm0812
Get a boost gauge!

You could try disconnecting the N75, it should put you into limp mode at 5psi. Give that a whirl and see if the problem persists.
You wanna help me buy one lol. I already disconnected it and it doesn't give me the erratic boosting or the strange sound. So I know my wastegate is ok and that the erratic boosting should be from the n75.

The only gauge setup I would get would be this one since it looks stock, but I can't see myself spending 150 bones for a damn boost gauge.

 
  #7  
Old 02-06-2011 | 03:28 AM
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mine is only boosting 5psi i proved it with 2 boost gauges i know my car is in limo mode but would the n75 be the issue ????
 
  #8  
Old 02-06-2011 | 03:29 AM
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Originally Posted by A4 2000
You wanna help me buy one lol. I already disconnected it and it doesn't give me the erratic boosting or the strange sound. So I know my wastegate is ok and that the erratic boosting should be from the n75.

The only gauge setup I would get would be this one since it looks stock, but I can't see myself spending 150 bones for a damn boost gauge.

as for you my friend i have a apex i el series boost gauge for sale ill let it go for 80 shipped its black face with red needle and white numbers i had it on my evo
 
  #9  
Old 02-06-2011 | 04:05 AM
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Originally Posted by Got_A4
mine is only boosting 5psi i proved it with 2 boost gauges i know my car is in limo mode but would the n75 be the issue ????
Have you checked all your vac lines? Do you have a cel? I've never heard of the n75 do anything but cause erratic boost, not completely cut off boost.

Originally Posted by Got_A4
as for you my friend i have a apex i el series boost gauge for sale ill let it go for 80 shipped its black face with red needle and white numbers i had it on my evo
Sounds nice but still not looking to spend that much.
 
  #10  
Old 02-06-2011 | 09:38 AM
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Originally Posted by A4 2000
Have you checked all your vac lines? Do you have a cel? I've never heard of the n75 do anything but cause erratic boost, not completely cut off boost.



Sounds nice but still not looking to spend that much.
your best bet is going to pep boys and picking up a autometer boost gauge from them they run about 50 ish
 



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