Clunk sound when doing 8-turns, steering rack?

[vwengineer]

Hello !

Since I replaced my struts bearings almost all my noises are gone. Car doesn't sound like an old wooden ship anymore, however, I still get one noise when doing 8 with the car (it's a part of the inspection that I have to pass soon). When turning left I don't have any noises but they when I turn right immediately to do the second part of the 8, I get a clunk when the steering wheel reaches or almost reaches the endstop and sometimes another one directly after, then no more noises even though I continue to drive with steering wheel fully turned right. I replaced:

- The tie rods ends (no play was felt by rocking the tie rod back and forth without the tie rod end)
- The struts bearings
- The springs
- The struts
- The stabilizer drop links
- Left CV joint

The noise was already there before I replaced anything. Now I'm not sure of what could be the origin of that kind of clunk (only happens once of twice directly after turning then no more noise, only happens on one direction. No noise over bumps, just when turning.

For me an obvious one is the steering rack but : I didn't feel any play on the tie rods/it doesn't happen when turning if the car is not moving. What do you think and what other tests could I do? I did not replace the knuckle ball joint because their boots were still good, could it be that? I also suspect the subframe bolts but I never touch them. Any other ideas?

Thanks!

 

[3carmonte]

Lift the entire front end and with someone in the drivers seat go through the steering range. As you alternately resist wheel movement on each side, outside of the car; have the driver stress against your resistance with steering effort until the clunk is felt/heard (hopefully). If you get a clue from this test, you may locate the origin. Use one of those cheap probing stethoscopes if you have to. I just hope it's not your steering rack.

 

[vwengineer]

Thanks mate, I will try that. I saw there was a repair kit with new bushings for the steering rack? Where does that came from?

I guess I could source a used rack and swap the electronics with mine if its the same generation so I don't have to code it? It's not possible to code with VCDS right?

To me it sounds more like the subframe is moving and but I also didn't touch the subframe bolts in 3 years and it only does this going on one side. Anyway I will try to retorque them to 70Nm and see.

 

[vwengineer]

A quick update, I had a look today. I could not reproduce that noise while being under the car I tried moving the tie rods with my hands while the rack was fully turned in the position where it makes noise, no play felt. I guess I should have removed the boot of the tie rod and check with a pry bar or something for play but I didn't. Instead I tried to tighten the subframe, 70Nm on the big bolts (18 or 16mm?), they were tight. Then I tried on the smaller ones (13mm) which connect to the anti-roll bar? They didn't feel tight (but they might have been at the correct torque spec) and some were clicking when turned, I tighten them a bit as I didn't know the torque specs (it was 20Nm+90° after checking).

Anyway, the noise seem to be gone

I am just wondering if those are also known to be problematic bolts causing subframe noises?

 

[Brigand253]

A quick update, I had a look today. I could not reproduce that noise while being under the car I tried moving the tie rods with my hands while the rack was fully turned in the position where it makes noise, no play felt. I guess I should have removed the boot of the tie rod and check with a pry bar or something for play but I didn't. Instead I tried to tighten the subframe, 70Nm on the big bolts (18 or 16mm?), they were tight. Then I tried on the smaller ones (13mm) which connect to the anti-roll bar? They didn't feel tight (but they might have been at the correct torque spec) and some were clicking when turned, I tighten them a bit as I didn't know the torque specs (it was 20Nm+90° after checking).

Anyway, the noise seem to be gone

I am just wondering if those are also known to be problematic bolts causing subframe noises?

Yes, the two main subframe bolts in the rear have been known to lose their clamping force over time. My guess is that these specific bolts continue to stretch from forces acting upon them and then you get subframe movement. One of the common cures was to replace them with the ones from the VW Passat. The Passat bolts are the same length of course, but more importantly are the same thickness throughout their length (whereas the ones that came on our cars thin down at some points along the bolt shaft). Why they designed them this way I don't know.

 

[mats__]

Hi,

I have a mk5 golf and some times I noticed a weird sound from front side when I am in very slow speed and turning the wheel to park. This noise is not produced when stationary and with high speeds. I have change suspensions, top mounts and silent block recently. However, this didn't fix the issue. The sound is recorded in this video ( occuring on 0:09-0:15)
Any idea what is causing this noise?
noise steering vw golf