Author Topic: Popping sound  (Read 1176 times)

Offline DCmk3

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Popping sound
« on: 29 September 2012, 14:40 »
So I have only had the car for about a month and there's a couple things I have sorted so far, but one that I can't figure out is the popping sound.. It's a 1.8 8valve motor.
There seems to be a popping sound coming from the two breather hoses which join to the inlet pipe.
If I pinch those breathers there's no popping sound but when they're open there's this constant popping sound almost like popcorn when the car is running.
Does anyone have an idea what causes that sound or if it's something bad?  :undecided:


Marked off the two breathers that the sound is coming from..




It's basically sounding like this;
http://www.youtube.com/watch?v=CJyVoRqiowI
« Last Edit: 29 September 2012, 16:40 by DCmk3 »

2014 Mk7 GTI - Littco L500

Offline tweed

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Re: Popping sound
« Reply #1 on: 29 September 2012, 17:26 »
Easy thing to do is take them off and see if they are blocked.

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Offline DCmk3

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Re: Popping sound
« Reply #2 on: 29 September 2012, 20:59 »
Turns out there was some nice caramel in the one pipe somehow, but only in a small section nearly blocking it entirely.  :huh:

2014 Mk7 GTI - Littco L500

Offline tweed

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Re: Popping sound
« Reply #3 on: 29 September 2012, 22:21 »
Clear it out with some petrol and job done

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Offline DCmk3

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Re: Popping sound
« Reply #4 on: 29 September 2012, 22:50 »
Cleaned out all the breathers, took the throttle body off and cleaned that too, it was covered in oil...
Now the revs seem to hang at about 1200 when you put the clutch in, then drop to 1000rmp on idle at operating temp, isn't it meant to idle lower?

2014 Mk7 GTI - Littco L500

Offline tweed

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Re: Popping sound
« Reply #5 on: 29 September 2012, 22:55 »
You have not put a vacuum hose back on.

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Offline DCmk3

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Re: Popping sound
« Reply #6 on: 30 September 2012, 12:20 »
I've checked all the vacuum lines, they're all on firmly but there's still a high idle..

2014 Mk7 GTI - Littco L500

Offline DCmk3

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Re: Popping sound
« Reply #7 on: 08 October 2012, 13:46 »
Solved the high idle, the Water Temperature sensor was dodgy, it was displaying the water temperature but when I unplugged it, the idle went to its correct place and doesn't stick anymore, replaced the sensor and it's working perfectly.

2014 Mk7 GTI - Littco L500

Offline WeekendMechanic

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Re: Popping sound
« Reply #8 on: 08 October 2012, 14:04 »
Good to hear mate  :wink: