HELP!! Clicking noise under hard acceleration

**007tig** · 29-04-2016, 11:41 AM

Hey guys!

First off, I have a 2011 Tiguan with 2.0T and Manual transmission that has done nearly 150 000km so far to date there have been no major mechanical issues. I blew a coil a few months ago but otherwise the Tig has been worry free until now.. Car is stock other than an aftermarket IC to help cope with Qld temps. The cooler has been on for over a year so I highly doubt this issue is related.

Anyway, last night I was coming home with the windows down and the radio up a little loud when I heard a noise whilst accelerating pretty hard in second gear out of a tight corner. The noise went away when I eased off the gas and didn't do it when I put my foot back down, albeit not as hard, and pointing in a straight line.

I turned off the music and attempted to recreate the noise; here's a summary of my observations:

* From experience with past FWD cars the noise sounds like a sick CV joint but it doesn't sound near as bad and sounds more like it is coming from the middle of the underside of the car

* I can do a full lock turn in either direction at without the noise occuring which leads me to think this is NOT CV related but hey, I'm no expert

* From what I can tell, the noise only happens when the AWD system would be kicking in to prevent loss of traction. I can take the same corner at speed but as soon as I give it too much power (where it would be at the edge of traction and I try to make it oversteer for example) it starts to make the horrible annoying clicking sound.

* It doesn't affect it's ability to get a bit sideways and doesn't effect control as far as I can tell. Obviously I don't want to push it while it's acting up so only really tried sliding a bit the one time last night. Had the windows been up I wouldn't even notice the noise I'd say; at this stage that's all it is, no vibrations etc.

* Definitely no feedback coming through the wheel or chassis to indicate a broken mount but I did read of someone who had a broken mount and didn't even realize..

Basically, if I baby the car the sound is not present but as soon as I give it gas and it get my boogie on, if it is a situation where traction may become an issue, it will click away until I back off the gas. I think it's Haldex or diff related..what do you guys think? The only thing remotely similar to my issue was described by a guy who swapped his Haldex controller and didn't top the fluid back up. He said he noticed he had this rattly pinging sound until he topped the fluid back up..

At the moment all I know is the Haldex and diffs need a fluid change so will start there. In the meantime I was hoping others may be able to chime in with any ideas they had.

I'll keep you guys posted on the resulting cause when I work it out..

**007tig** · 29-04-2016, 03:29 PM

Update:

Pretty scary when the VW service guy argues with you saying the haldex and diff oil are one and the same. Only an image showing both haldex and diff drain/fill plugs would convince him otherwise.. They are now seeking the Castrol Syntrax for the diff as I showed them the image of what I was after.

GEEEEZ!

**Bora Sport** · 29-04-2016, 04:30 PM

A bit of a worry for sure. I remember when I took my Bora in for the haldex oil change it was the first one that they had ever done. It was many years ago though. I was going to suggest the diff oil. VW don't seem to have any recommendations to change it but after around 150,000k's my Bora was making some horrible noises when it was hot (say after 100k's highway) and then doing turns. It actually sounded like it had a tooth missing. I thought I was up for big dollars but my mechanic mate said Commodores did the same thing when they needed the diff oil changed. He was right. New oil in and my worries were gone.