Can anyone see from this vcds log why no start ?

Hi All,

My Octavia 2.0 tdi aut. 2005, is cranking a looong time every morning. And also sometimes when hot. But can also start immeadiately when hot. I suspect fuel pressure is diminishing overnight, or somebody mentioned the lift pump - but im not sure there is a lift pump in my car.

I have logged the engine group 5 from cold engine, but i cannot interpret the values in field 3, regarding the camshaft and the crankshaft sensor. It ssems that the fuel is injected all the time ? Is the sensor data then ok ? Why dont i get an "004" engine running ? Its a BKD engine.

I start cranking at 3.54 but first at 5.56 the engine starts. Its injecting fuel the hole time, so why doesnt it start ? Timing is spot on as torsion value is 0.0.

Is the "start syncronization" values ok during crank ?

Group A: '005
Engine Speed Start Injection Start Coolant
TIME (G28) Quantity Synchronisation Temperature (G62)
Marker STAMP /min mg/str ｰC
0.00 0 16.2 2.0 18.0
0.09 0 16.2 2.0 18.0
0.19 0 16.2 2.0 18.0
0.28 0 16.2 2.0 18.0
0.38 0 16.2 2.0 18.0
0.47 0 16.2 2.0 18.0
0.58 0 16.2 2.0 18.0
0.67 0 16.2 2.0 18.0
0.76 0 16.2 2.0 18.0
0.85 0 16.2 2.0 18.0
0.94 0 16.2 2.0 18.0
1.03 0 16.2 2.0 18.0
1.14 0 16.2 2.0 18.0
1.23 0 16.2 2.0 18.0
1.32 0 16.2 2.0 18.0
1.42 0 16.2 2.0 18.0
1.51 0 16.2 2.0 18.0
1.60 0 16.2 2.0 18.0
1.72 0 16.2 2.0 18.0
1.81 0 16.2 2.0 18.0
1.90 0 16.2 2.0 18.0
2.00 0 16.2 2.0 18.0
2.09 0 16.2 2.0 18.0
2.18 0 16.2 2.0 18.0
2.30 0 16.2 2.0 18.0
2.39 0 16.2 2.0 18.0
2.48 0 16.2 2.0 18.0
2.57 0 16.2 2.0 18.0
2.66 0 16.2 2.0 18.0
2.76 0 16.2 2.0 18.0
2.87 0 16.2 2.0 18.0
2.96 0 16.2 2.0 18.0
3.06 0 16.2 2.0 18.0
3.15 0 16.2 2.0 18.0
3.24 0 16.2 2.0 18.0
3.34 0 16.2 2.0 18.0
3.45 0 16.2 2.0 18.0
3.54 84 16.2 16.0 18.0
3.63 147 16.2 32.0 18.0
3.72 147 16.2 3.0 18.0
3.81 126 16.2 3.0 18.0
3.90 210 16.2 33.0 18.0
4.01 273 16.2 33.0 18.0
4.10 315 16.2 3.0 18.0
4.19 315 16.2 3.0 18.0
4.29 315 16.2 3.0 18.0
4.38 357 16.2 3.0 18.0
4.47 336 16.2 3.0 18.0
4.57 336 16.5 3.0 18.0
4.66 336 16.7 3.0 18.0
4.75 336 17.0 3.0 18.0
4.84 357 17.3 3.0 18.0
4.93 420 17.6 3.0 18.0
5.02 420 17.8 3.0 18.0
5.13 357 18.4 3.0 18.0
5.22 378 18.7 3.0 18.0
5.31 525 18.9 48.0 18.0
5.40 630 19.2 48.0 18.0
5.49 693 19.5 48.0 18.0
5.59 1029 16.7 48.0 18.0
5.70 1218 16.7 48.0 18.0
5.79 1197 16.7 48.0 18.0
5.88 1113 16.7 48.0 18.0
5.97 1008 16.7 48.0 18.0
6.06 987 16.7 48.0 18.0
6.15 945 16.7 48.0 18.0
6.26 924 16.7 48.0 18.0
6.35 903 16.7 48.0 18.0
6.44 882 16.7 48.0 18.0
6.53 882 16.7 48.0 18.0
6.62 840 16.7 48.0 18.0
6.71 840 16.7 48.0 18.0
6.82 798 16.7 48.0 18.0
6.91 819 16.7 48.0 18.0
7.00 819 16.7 48.0 18.0
7.09 819 16.7 48.0 18.0
7.18 819 16.7 48.0 18.0
7.27 819 16.7 48.0 18.0
7.38 819 16.7 48.0 18.0
7.47 819 16.7 48.0 18.0
7.56 819 16.7 48.0 18.0
7.65 840 16.7 48.0 18.0
7.74 819 16.7 48.0 18.0
7.83 840 16.7 48.0 18.0
7.95 819 16.7 48.0 18.0
8.04 819 16.7 48.0 18.0
8.13 819 16.7 48.0 18.0
8.22 840 16.7 48.0 18.0
8.31 819 16.7 48.0 18.0
8.40 819 16.7 48.0 18.0
8.50 840 16.7 48.0 18.0
8.59 819 16.7 48.0 18.0
8.69 819 16.7 48.0 18.0
8.78 819 16.7 48.0 18.0
8.87 819 16.7 48.0 18.0
8.96 819 16.7 48.0 18.0
9.07 840 16.7 48.0 18.0
9.16 840 16.7 48.0 18.0
9.25 819 16.7 48.0 18.0
9.34 819 16.7 48.0 18.0
9.43 819 16.7 48.0 18.0
9.52 840 16.7 48.0 18.0
9.63 819 16.7 48.0 18.0
9.72 819 16.7 48.0 18.0
9.81 819 16.7 48.0 18.0
9.90 819 16.7 48.0 18.0
9.99 840 16.7 48.0 18.0
10.08 840 16.7 48.0 18.0
10.19 840 16.7 48.0 18.0
10.28 840 16.7 48.0 18.0
10.37 840 16.7 48.0 18.0
10.46 819 16.7 48.0 18.0
10.55 840 16.7 48.0 18.0
10.64 819 16.7 48.0 18.0
10.75 819 16.7 48.0 18.0
10.84 819 16.7 48.0 18.0
10.93 840 16.7 48.0 18.0
11.03 819 16.7 48.0 18.0
11.12 819 16.7 48.0 18.0
11.21 840 16.7 48.0 18.0
11.31 840 16.7 48.0 18.0
11.40 819 16.7 48.0 18.0
11.49 819 16.7 48.0 18.0
11.58 819 16.7 48.0 18.0
11.67 819 16.7 48.0 18.0
11.76 819 16.7 48.0 18.0
11.87 819 16.7 48.0 18.0
11.96 819 16.7 48.0 18.0
12.05 819 16.7 48.0 18.0
12.14 840 16.7 48.0 18.0
12.23 819 16.7 48.0 18.0
12.33 819 16.7 48.0 18.0
12.44 819 16.7 48.0 18.0
12.53 819 16.7 48.0 18.0
12.62 840 16.7 48.0 18.0
12.71 840 16.7 48.0 18.0
12.81 840 16.7 48.0 18.0

I believe the BKD is a Pump Duse engine. You should have a Tandem Pump and also a lift pump inside the fuel tank. Either one of them is losing prime after the car aits for a couple of hours. I dont think it will show on the vcds..

Carlos_TJ said:

I believe the BKD is a Pump Duse engine. You should have a Tandem Pump and also a lift pump inside the fuel tank. Either one of them is losing prime after the car aits for a couple of hours. I dont think it will show on the vcds..

Click to expand...

If the interweb didn't lie to me, that would be correct. Notice the Tandem pump and unit injectors.



Also the ECU will not throw a code for a clogged fuel filter.

A Torsion value of Zero can mean that torsion is out of range. If Torsion does not change at least some when the engine is revved, it means that the Torsion is out of range so the ECU assumes Zero Torsion.

Thanks for Your suggestions.

I have also suspected the fuel pressure, but it can also crank a long time, if it only has been stopped for 5 minutes. Thats why i suspected either the cam or the crankshaft position sensor ?

Regarding the torsion value. Before hand it was -1.5, and i adjusted it to 0.0. Has also tried +1.5. On my old 1.9 the torsion value fluctuated in idle, all the time. This one is dead on zero in idle. If i accelerate fast, the value raises to +1.0.

Should the value change if i rev the engine at standstill ? Im pretty sure its not out of range, as i have adjusted the timing as described, but maybe the camshaft sensor has know died on me. Can i check that by adjusting the timing again, and check if the value changes to like -1.5 ?

Some guy on another board told me that elsapro specifies that the torsion value in idle hot engine should be set to between 3 and 4. Thats rubbish right ?

Mivini said:

Should the value change if i rev the engine at standstill ? Im pretty sure its not out of range, as i have adjusted the timing as described, but maybe the camshaft sensor has know died on me. Can i check that by adjusting the timing again, and check if the value changes to like -1.5 ?
Some guy on another board told me that elsapro specifies that the torsion value in idle hot engine should be set to between 3 and 4. Thats rubbish right ?

Click to expand...

Yes it should. What it is doing is showing the slight amount of stretch in the timing belt that naturally occurs when you rev the engine. If the value does not change when you rev, Torsion is set out of range.

Torsion is always set at idle on a warm engine and can be optimized some. Just set it at fairly close to zero and then move on. IIRC Torsion can be anywhere from say Minus 3 to Plus 3 and not effect starting.

All you ever wanted to know about Torsion:
http://forums.tdiclub.com/showthread.php?t=336279&highlight=Torsion
Have you replaced you fuel filter and checked pressure from the lift pump and Tandem pump?
If you point the front of the car down hill when you park over night is the car easier to start in the morning?

I don't think it's a timing problem, the torsion value shows it's ok.

Usually when it takes more turns than usual is fuel related.

I would start by measuring the pressure on the port of tandem pump. Failed tandem pumps usually take some turns to build up pressure, and all 4 injectors only open after some amount of pressure.

Check this:

http://pics.tdiclub.com/data/517/PD_fuel_delivery_check.pdf