VCDS values and BKD timing to smooth idle!!!

--AUDI--

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I am currently trying to sort out the rough idle on my A3 s-line 2.0 Tdi (BKD)

I have borrowed a lead from a user on here to check some values after reading up on this quite a bit and it seems I may need to adjust my front cam but I am wondering if someone can have a look at the VCDS readings for me to confirm this.

I have taken 3 snap shots of the readings from measuring blocks 4,13 and 15

Do the injector quantities seem ok?
Should the torsion value be 0?
And I believe my engine torque is too low at idle as is my fuel consumption.

These readings were all taken with engine at normal operating temperature, also the rpm at idle constantly fluctuates between 819 and 840 rpm.

Symptoms I have are a slight hard start, juddering at idle and extremely good fuel consumption which all seem to point to bad cam timing.

Image1 Image2 Image4

So basically the question is is it just the front cam that will need adjustment and which way?

Any help on this would be greatly appreciated
 
Also whilst reading up on this it seems that both cams should look roughly the same with regards to the oval adjustment bolt holes, on mine they seem to be opposite ends of the adjustment.
 
Injectors deviations look very good!
Torsion supposed to be 0, but you can experiment.

Front cam adjustment change TorsionValue.
Rear cam change consumption.

I would leave torsion alone, and play with exhaust camshaft (rear) to get 0.6l/h.
 
Injectors deviations look very good!
Torsion supposed to be 0, but you can experiment.

Front cam adjustment change TorsionValue.
Rear cam change consumption.

I would leave torsion alone, and play with exhaust camshaft (rear) to get 0.6l/h.

Hi thanks for the reply, any idea which way to turn the sprocket to increase the consumption up to 0.6?

also can you "play around" with out causing any real problems?
 
Following this thread with interest. I have the same symptoms as you. My torsion value is at -2.9 though. Hopefully this is my prob. Looking to adjust the front cam next weekend. My fuel flicks from 0.4l/h to 0.2 thinking this is prob also a little low.
 
Following this thread with interest. I have the same symptoms as you. My torsion value is at -2.9 though. Hopefully this is my prob. Looking to adjust the front cam next weekend. My fuel flicks from 0.4l/h to 0.2 thinking this is prob also a little low.

I will let you know the outcome, looking to do the adjustments maybe next weekend, yes the fuel consumption should be 0.6 l/h and torsion near 0
 
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Hi thanks for the reply, any idea which way to turn the sprocket to increase the consumption up to 0.6?

also can you "play around" with out causing any real problems?
If I remember correctly, I turned the center bolt clockwise to increase l/h.
Few degrees/mm both ways shouldn't make anything bad. Mark your initial position :)

After all, just try to change idle rpm to cure juddering.
 
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Do you need to lock the cams to undo the 3 13mm bolts?
 
Just to let you know I did the adjustment at the weekend. Found it pretty easy to do. Although I couldn't get the torque wrench on one of the 13mm exhaust bolts. Due to the brake resivour being in the way. So tightened with a ring spanner and marked with a marker pen and turned the engine briefly to bring the bolt out of the way. Got my torsion value to 0 from - 2.9 and my idle to 0.6 lph from 0.2-0.4.
Has made a massive difference to the car. So much smoother at idle and the car feels much more healthy. No longer feels like it bogs down when pulling away. And has so much more power. Before past 3k was flat but now it pulls hard right up to 4k prob past. Easy free fix that has transformed the car.
 
Thats great, I hope to get my car done this week, have been a bit busy this weekend!
 
Finally got round to doing mine last night, adjusted rear cam clockwise to bring the feeling at idle up to 0.6 l/ph and the rough idle has gone!

Did you notice your fuel consumption go up by much?
 
Just to let you know I did the adjustment at the weekend. Found it pretty easy to do. Although I couldn't get the torque wrench on one of the 13mm exhaust bolts. Due to the brake resivour being in the way. So tightened with a ring spanner and marked with a marker pen and turned the engine briefly to bring the bolt out of the way. Got my torsion value to 0 from - 2.9 and my idle to 0.6 lph from 0.2-0.4.
Has made a massive difference to the car. So much smoother at idle and the car feels much more healthy. No longer feels like it bogs down when pulling away. And has so much more power. Before past 3k was flat but now it pulls hard right up to 4k prob past. Easy free fix that has transformed the car.

Finally got round to doing mine last night, adjusted rear cam clockwise to bring the feeling at idle up to 0.6 l/ph and the rough idle has gone!

Did you notice Your mpg go up?
 
Most say consumption becomes better when on idle it "eats" more fuel :p
 
Finally got round to doing mine last night, adjusted rear cam clockwise to bring the feeling at idle up to 0.6 l/ph and the rough idle has gone!

Did you notice Your mpg go up?
Hi. My my mpg didn't change to much. And tbh isn't that great. My gf uses the car to go to work and back. Down small country lanes. My mpg is around 40mpg. Seems a little low but will test on a long run at the weekend.
Did you adjust the front cam at all?