Fault or normal?

[KrisKrk]

Hi everyone,
Got an issue with my A6 that is happening more often now.

About 9-10 months ago, when stopped on traffic lights my car suddenly shook and revs bumped up by 100-150.
Usually they about 800 when stationery and the car was warmed well enough as driven around 18miles.
Moved off and made maybe another half a mile to the work car park.
Got out of the car and noticed radiator fan on.
When came back and started the car, all was as it should until driven away. Car showed the same symptoms and more. Was more agile by throttle response.
It felt like it was remapped, more powerful with more torque.
Also could hear like turbo spin (tu lu lu lu) when changing the gear from 1 to 2 and to 3, not higher.
All this stopped after 10-15 miles on the way home.

Now, same things happening around every 200 miles.

After the first time, car was checked with computer but nothin showed up or it didn't had any error codes.

When I took it for the emission recall, got it diagnosed by Audi and again nothin came from the memory. Been advised that it could be dpf regenartion process as mostly driving in traffic so it cannot be done by default system when it needed.

I do drive it short distances few days in the week and others around 20 miles but mostly in traffic.

Any ideas what it might be or what to look out for?
It is hard to do full diagnostic when it happens as all garages are shut by the time I'm back from work.

Appreciate any input

 

[Broken Byzan]

doers sound like regen to me

 

[Mollygoogle]

Yup, DPF regen. Get rid of the DPF

 

[KrisKrk]

But should it make a turbo spool sound?
does it also mean that dpf is so clogged up that it need it to regen so often?

 

[Simon968]

Take it for a decent run out, keeping above 2500 RPM for about 15 - 20 minutes. That should reduce the level of soot in the filter.
It maybe that your short runs are not allowing the DPF to do a full regen.
I think that you can read how full the DPF is using VCDS.

 

[KrisKrk]

Thanx all for indications.
Simon968 I did read about it already here and elswhere and done it once.
Drove in the 5th on the motorway with about 60mph to allow regen at shorter distance.
Will do it every so and often but will eventually get rid of the dpf.

 

[KrisKrk]

Just a recap,

Got the DPF cut out done by Bobby Singh.
Also, some BHP and torque increase.

Happy with it all as it just revs like mad, this machine.

Problem should go away now but will report after few 100's miles to be sure.

 

[KrisKrk]

As said earlier, all symptoms described in the beginning are gone.

Covered about 500 miles and not a single rev increase. It look's like dpf was clogged up to the level it needed regen but not enough to throw out the warning light on the dash.

To top it all up, the sound of the turbo spool (tu lu lu lu) was actually a clutch over spin and slipping.
As described, only when changing the gear from 1 to 2 and rarely 2 to 3, when forced regen was taking place, car was very agile and acting like chipped/remapped. Had more power, quicker throttle response and torque.
Occasionally, it was connected with revs jumping from 2k-3k when changing 3rd to 4th gear and car could not drive off as it should with that power.

Unaware of what it's going on, was driving normally, avoiding this to happen, if possible.

Now, after dpf gone and remap done, Bobby Singh, who did this magnificent job for me, recommended the clutch replacement. It's slipping and cannot cope with more torque, after the remap and look's like it was already wearing out from long time ago.

Been recommended Sasch Clutch kit. Does anyone know any reasonable priced place to get the whole kit with flywheel?

 

[Simon968]

Try Euro Car Parts or Car Parts 4 Less (both actually the same company, but CP4L usually cheaper) for your clutch.
CP4L has a 12.5% off sale on this weekend.

Both of the above sell through eBay too and there can be some good offers to be had.

 

[KrisKrk]

ECP have only LUK clutches. Will try the other one. Thanx Simon

Edit: Yup, CP4L have the same LUK ones.

Sasch website doesn't even have clutch kits for my car.

Advised that performance clutch as had to decrease the torque of the remap.
Bobby Singh advised it will be better to prolong the clutch life until find the right replacement.
After clutch replacement, can come back to him to get the original map done.

 

[KrisKrk]

Might be silly question: Does the flywheel need to be also replaced with the whole clutch kit?

Found the set on Sasch Performance website but it's nearly 1300 euro

 

[Simon968]

I've fitted LUK clutches in the past to my old Golf GTI and they were fine. I think that they were original equipment at one time on VWs along with Sachs.

Flywheel probably only really needs to be replaced if it is noisy, although it is good preventative maintenance I suppose to change with the clutch as it is the same job to change the clutch or the flywheel.

 

[KrisKrk]

Thank you Simon,
Will probably have to go with LUK as my only option.

Dont want to pay silly money for a high class performance clutch on the car that cannot cope with few additional bhp/torque and need new clutch after just 90k miles

 

[KrisKrk]

Right, just came back from short drive of about 10-15 miles and the revs popped up for the first time since remap and dpf delete.

Yesterday I was driving about 10 miles in traffic so it wasn't smooth, continuous drive. Maybe the engine got confused and decided to increase the revs?

Like previous symptoms just happened but without fan going mad. Probably as there is no dpf.
Car is even more aggressive and throttle responsive than usual.

This didn't happened after about 800 miles.

Anyone can have a clue what the revs increase be related to?


Sent from my iPhone using Tapatalk

 

[KrisKrk]

Ok, it was me. DUH

Missus asked me to direct the air onto her feet's at the back and started to fiddle with the buttons while on motorway. Accidentally switched on the AC and did not seen that for days. Forehead hurts me till now from the face palm I did then.

AC off and revs are as they should.