Mysterious Knocking Sound

FIXED BY INSTALLING SUB FRAME SHIMS/BOLTS

**3/11/2012 Update**

Finally figured out this noise yesterday when I was working on the car. I had the strut mounts/bearings replaced a week or two ago which seemed to, once again, eliminate the noise. That lasted all but a day or two.

Fast forward to yesterday afternoon. I was servicing the TyrolSport guide pins on the front calipers (remove, clean, re-grease, re-install). When I got to the last/most difficult one to re-install due to my lovely brake line being in the way, I noticed that it was significantly more loose than the other guide pins. Lubed it up, installed and tightened appropriately, and went on a drive. Zero noise. ZERO.

I'm aware that not too many people have this caliper stiffening kit installed so this noise may just be isolated to my car, but it's worth checking regardless if they've ever been removed or anything like that from your own car. Lets hope I don't have to update this thread ever again. Stupid guide pin.

**9/23/2011 Update**

Bumping this as my lovely clunking/cracking sound is still present. Here's what else has been done since my last update:

-All sub-frame bolts replaced and torqued
-Swapped out rear LCA bushing with Whiteline ALK
-Replaced front LCA bushing with OEM
-Replaced bolts/nuts for FSB brackets

Upon examination of the stock rear LCA bushing housing it was clear that when I bottomed out in Atlanta that they made contact with the ground. The front facing lip of the housing was marred and bent backward at a 75* angle vs. the flat 90* a brand new one would be (if using the car from front to back as a 180* line). I've acquired a used set of FSB brackets to see if perhaps the ball joints are going bad or already bad, but there's no visual indication that they have. How could I check this?

Other thoughts:

-Ball joints?
-Tie rod end?
-CV joint?
-Some other part of the car that I don't know could be causing this sound?

Symptoms listed above in original post are all still the same, however, the loudest cracking/clunking occurs when making right-hand turns. I verified this last night by making sharp turns in col de sacs

I also have the Unibrace XB and UB installed on the car, but the noises happen nowhere near those areas. I don't want to put any additional money towards the car hoping to fix this issue until I know what it actually is. The sound can also be clearly heard outside. Perhaps louder there than inside the car itself.

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Before anyone says it's my sub frame allow me to share what I've tried already.

I noticed a clunking sound coming from the front right side of the car when making slightly aggressive right turns. First thought was my sub frame bolts. Took it to my buddy at the dealership and he said everything looked good. In addition, whenever this knocking sound occurs there are times where it will also make a creaking noise. These are the other areas I've checked:

-Sub frame/pendulum mount
-Unibrace UB bolt points
-Tyrol brake bushing

The issue appears to have gotten worse where now even if I go over speed bumps, slow down (braking), or go over uneven inclines at a slow rate of speed it makes the noise (level of sound varies every time). On several occasions while turning right the noise has traveled from the right side of the car to the left side where I feel it through my feet on the floor of the car.

Just looking for insight as far as what else I could check. As far as I can tell the car feels okay (nothing loose), but who knows...I drive it every day.

Your control arm bushings are cracked. Replace them with Whitleline Poly bushings

Would that be the same as the WALK?

Holy shit, I am having this exact same problem. let me know what happens.

If it is in fact the control arm bushings i think this would be a good upgrade as well

http://www.ecstuning.com/Flyer-ECS_MKV_Stage3_BBK/ES514232/

Just got home a few minutes ago and took a look at the control arm bushing with a flash light. I didn't see any damage to the bushing itself. Would the crack be clearly visible upon inspection? I couldn't see much when looking at it from the front of the car since the control arm was in the way, but the back side was clearly visible and I didn't see anything glaring.

Edit: Perhaps Jimithing was referring to these: http://www.ecstuning.com/Volkswagen-Golf_V--2.0T/Search/Whiteline/ES514164/

Would make more sense.

Sub'd. I too have this same clicking noise.

Did some more poking around and it appears that it could potentially be the upper strut mount if the control arm bushing turn out to be okay. I'm going to let the thread sit until tomorrow morning/afternoon to see if anyone else has suggestions.

i have the same sound but mine is when braking

I think the W.A.L.K. replaces them completely

I suspect my issue was different, because I only heard the clunk when I was turning very hard at speed, or from lock to lock in the parking lot... but I'll mention it just in case.

The dealership wound up replacing my steering rack, and I've been clunk free ever since.

So apparently if the LCA (lower control arm) bushing has gone bad you can check it by dong the following:

-Jack up one corner of the car
-Grab the wheel at 3 o'clock and 9 o'clock
-Shake back and forth

If it moves at all either your bushings or tie rod ends are bad. To confirm which, you will need to lay under the car while someone else shakes the wheel to see where the play is.

This was taken from another forum. I'll give this a shot when I get home from work today

thanks for the insight. im gonna have to try this.

Well...checked for play using the steps listed above and there's no movement. So while the car was in the air I decided to take a peak at the sub frame and other components just to see if anything stood out. Something did.

Just before I was going to crawl out from under the car I noticed one of the sub frame bolts had some black stuff between the bottom of the bolt head and the sub frame itself. When I put my hand on it to turn it...I was able to turn it freely by hand! And not just a little...a lot. Then I gently pulled down on it to find that the head of the bolt is busted. This is good news to me because it means that I've isolated my problem and prevented myself from having to purchase new LCA bushings.

The bad...well...I need a new bolt and I have to find a way to get the old one out. I'll figure something out. For anyone who is curious which bolt it was, mine turned out to be the one closest to the front of the car on the passenger side.

Mystery solved - sub frame after all.

good job finding it. what do you think caused it

If I had to guess then I would say it was spurred by an unpleasant bottom-out experience I had in Atlanta. Was driving about 15mph on a service road near some mall and didn't even see the drop. Got some nasty damage on the bottom side of the lip, scraped the Unibrace UB a little and I'm guessing it was also enough to do some damage to the bolt. A few weeks ago I hit a really nasty bump in the road on my way to work and that's probably was made it snap completely as it got worse from then on. I just gotta find the part number for that particular bolt so I can get it replaced.

Time to start dodging those road hazards more