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Model specific boards => Golf mk4 => Topic started by: Quackers on 19 August 2014, 10:01

Title: If anybody can diagnose this noise, I'll be seriously impressed (vid inside)
Post by: Quackers on 19 August 2014, 10:01
Hi guys

The car has developed a rattle/knocking that I can't get my head around. Has absoloutely no effect on performance - haven't taken any logs on Vagcom or anything yet but car seems to be running as it should be. After doing a bit of research, I decided to replace the timing belt, waterpump and tensioner - I read on numerous occasions about the timing belt tensioner becoming noisy with old age. This hasn't altered the noise at all.

On further inspection, the noise seems to be coming from the passenger side of the engine, towards the bulkhead. However its difficult to be sure as the engine bay is a noisy place at the best of times.

Finally - the noise doesn't change in tone with the clutch depressed, or when the car is in any gear. Video:

(http://i102.photobucket.com/albums/m112/Max_____xaM/th_Video.mp4) (http://i102.photobucket.com/albums/m112/Max_____xaM/Video.mp4)

At the begining of the video, I'm putting the accelerator straight to the floor and letting go quickly - this is when the noise is worst. Then I build revs progressivly and the noise isn't present. You'll get the idea from the video anyway I hope.

Any help would be greatly greatly appreciated, I'm at my wits end and can't use my car :cry:
Title: Re: If anybody can diagnose this noise, I'll be seriously impressed (vid inside)
Post by: SI74 on 19 August 2014, 11:45
Is all the engine mounts looking ok?

Never hear of anything like this before. Seams to be when you put the engine under load.
Title: Re: If anybody can diagnose this noise, I'll be seriously impressed (vid inside)
Post by: Quackers on 19 August 2014, 11:48
Yeah thats right! Nope, engine mounts are fine. Replaced the dogbone for a polybushed one yesterday (and was THS Stage 1 before) and upper mounts are both THS stage 1 and about 18 months/15k miles old.

Miffed!
Title: Re: If anybody can diagnose this noise, I'll be seriously impressed (vid inside)
Post by: mcgee9t2 on 19 August 2014, 12:45
cannot view the video at work says its been deleted or re-named?

but, based on your description, id say check the down pipe, i had a knoking that i could not work out where it was from, was somewhere towards centre/pass side of the car near the bulk head, but noone could work out what it was including a garage, anyway, after about 3 weeks i took it back to the garage and asked to borrow a ramp, checked down pipe and it was slightly loose.

could be the same problem, my mate had a clunking noise that he couldnt work out what it was shortly after and turned out to be the same thing...
Title: Re: If anybody can diagnose this noise, I'll be seriously impressed (vid inside)
Post by: brianpologti on 19 August 2014, 13:27
Is ur maf  disconnected from tip ? looks it , ur engine sounds rough , sounds like u got a big boost leak and the idle is dropping to low
Title: Re: If anybody can diagnose this noise, I'll be seriously impressed (vid inside)
Post by: Quackers on 19 August 2014, 16:00
Downpipe? Interesting. Heres to hoping. I'll check it. Presumably you mean down pipe to turbo bolts?

Yeah I left the air box disconnected, was having a look/listen with it removed and didn't plug it back in because the induction noise wasn't helping capture the problem sound on the video.

P.S. Video should still be working - going okay for me. Thanks for replies so far!
Title: Re: If anybody can diagnose this noise, I'll be seriously impressed (vid inside)
Post by: Bellend on 19 August 2014, 19:48
Engine mounts tight and new bolts used??
Title: Re: If anybody can diagnose this noise, I'll be seriously impressed (vid inside)
Post by: Dalo Harkin on 20 August 2014, 12:19
are you just revving the engine in the video or driving it?
are the gear linkages hitting anything or being impeded by anything? (assuming you are driving and not stationary)