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Author Topic: Periodic knocking on idle  (Read 1675 times)

Offline Ash_89

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Periodic knocking on idle
« on: February 27, 2018, 06:04:59 pm »
When car is stationary I have a intermittent knocking noise coming from the engine  that comes and goes every 3 seconds
The cars gear changes are jerky aswell the car jerks when lifting the clutch back up 
Manual trans
Bwa gti 2007


Offline pudding

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Re: Periodic knocking on idle
« Reply #1 on: February 28, 2018, 11:37:46 am »
Get a long metal bar or screwdriver and use it as a stethoscope to narrow down where the noise is coming from.   


2007 ED30 | 2009 TDI 140 | 2016 BMW 330D

Offline Ash_89

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Re: Periodic knocking on idle
« Reply #2 on: March 02, 2018, 01:07:55 pm »
I think it’s something to do with the clutch or flywheel
There’s a slightly clanky knock that only is apparent when cold but goes away when I press the clutch pedal

Offline _dubstar_

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Re: Periodic knocking on idle
« Reply #3 on: March 04, 2018, 12:52:47 pm »
That's exactly the same symptoms I have on an 2005 A3. I had it diagnosed as Dual mass flywheel, it sounds like a brick in a washing machine when cold but not there under load or if you depress the clutch. Been like it for ages, its on my list of things to do but still drives fine for now, I don't have any gear change issues...yet. I know it won't get better but I'm in denial, plus it will be a good excuse to drive the V5 when it goes.