Won’t start. No fault codes

Thank you very much Catfood12

I will certainly do that tomorrow and let you guys know how we get on
I don't think you'll see anything, as the injection duration is at zero. When you said earlier it starts and runs on Easy Start, do you mean you have to keep feeding on Easy Start to keep it running, or once it's started on Easy Start, it will then run as normal ?
 
I don't think you'll see anything, as the injection duration is at zero. When you said earlier it starts and runs on Easy Start, do you mean you have to keep feeding on Easy Start to keep it running, or once it's started on Easy Start, it will then run as normal ?
Yes we have to keep feeding on easy start to keep it running once we stop feeding the easy start the van stops
 
Not another one of these is it;


Diagnose Dan where a VAG TDI engine would only start from cold after a very long crank. Turned out to be the variable valve timing actuator losing oil and retarding the cam to a point where it wouldn't start. I was surprised at the time that it wouldn't at least splutter and fire. Afterwards I wondered if that was a safety feature that the thing wouldn't start at cranking revs with a so far retarded cam. There was no error codes on that either, and Dan found it (we diagnosed it together! :grin bounce:) by the number of pulses from the crank reluctor between TDC and the cam at first crank, and when it finally started. That could explain the queer phase angle here ...
 
The photos of the timing belt you posted when showing the timing locking pins don’t look like a new timing belt, looks to be slightly worn.
Are you sure it is the correct timing belt?
 
Wondering if the engine hasn't yet updated the value and thus refuses to fire the injectors.

IDE00182Camshaft adaptation intake bank 1: phase position

Certainly worth doing!

Has it been seriously cranked after the latest timing belt adjustment?
Perhaps a few tries to crank (possibly logging too)?

Then finally another full blockmap capture so we can see if anything in the data has started to change?
Sorry @mmi Only seeing this now, yes it's been cranked quite a few times since the timing belt was adjusted. I'll get it all put back together tomorrow and do another bookmap and another log and will post up. Thank you very much
 
Ok, all we're left with is that the inlet cam is misaligned. The timing belt drives the exhaust camshaft, which we know is timed up OK. The camshaft position sensor however picks up only on the inlet camshaft, which is drive by spur gears at the back of the head via the exhaust camshaft. See diagram below.



cams.JPG
I reckon they've installed the inlet camshaft incorrectly and it's timed up wrong, hence the incorrect phase angle being reported, so ECU won't fire the the injectors, as the thing is so far off the end stops of the map, similar to the other belt related non-starts. It's far enough out to stop the ECU working out when to send the fuel, but perhaps only a tooth or two, so close enough that the motor will run on Easy Start.
 
The photos of the timing belt you posted when showing the timing locking pins don’t look like a new timing belt, looks to be slightly worn.
Are you sure it is the correct timing belt?
Hi DXX we are in no way mechanic's this is the way we received the van from a so called specialist and we were told there was a new timing belt kit fitted
 
Ok, all we're left with is that the inlet cam is misaligned. The timing belt drives the exhaust camshaft, which we know is timed up OK. The camshaft position sensor however picks up only on the inlet camshaft, which is drive by spur gears at the back of the head via the exhaust camshaft. See diagram below.



View attachment 139945
I reckon they've installed the inlet camshaft incorrectly and it's timed up wrong, hence the incorrect phase angle being reported, so ECU won't fire the the injectors, as the thing is so far off the end stops of the map, similar to the other belt related non-starts. It's far enough out to stop the ECU working out when to send the fuel, but perhaps only a tooth or two, so close enough that the motor will run on Easy Start.
Thanks again the van is booked in with another mechanic on Tuesday, I'll be sure to pass on all the info yous guys have provided to him. Really appreciate all the help
 
Looking at the cam you should try and get the pin in the centre of the elongated hole. Are you sure the crank is lining up as it should? Everything needs to be lining up. Worth spending time getting it right.
It’s not unheard of for a mechanic to replace an item matching it to what is fitted rather than checking the correct part number.
Just wondering if the first timing belt renewal which resulted in a failed tensioner was a result of an incorrect belt.
The subsequent replacement could have been made by simply matching to the original belt rather than checking the correct part is fitted.
Just a stab in the dark.
 
Sorry @mmi Only seeing this now, yes it's been cranked quite a few times since the timing belt was adjusted. I'll get it all put back together tomorrow and do another bookmap and another log and will post up. Thank you very much

Thanks. I would expect that if we do not see injectors to start firing in 2-3 seconds any further cranking won't do it either.

Here is a slightly modified proposal for the next logging during the cranking. Now the prime suspect "IDE00182 Camshaft adaptation intake bank 1: phase position" is also included on this "short list.

Either tick the following manually or preferably use attached preformatted file as explained further down.
The file must have extension .U01 thus remove the extras from the file name.

IDE00021Engine RPM
IDE00182Camshaft adaptation intake bank 1: phase position
IDE00347Air mass: actual value:
IDE00351Main injection: start of activation
IDE00352Main injection: duration of activation
IDE00407Rail pressure regulation: status
IDE00416Starter control: terminal 50 feedback
IDE00589Fuel pressure
IDE07822Fuel pressure regulator valve: activation
IDE07824Tank-internal presupply pump 1 bank 1: activation
ENG113754-ENG113670P_L_Aps_synchronised_origin-Sync_origin
ENG113757P_L_Aps_timeout_detected

Once you have ticked the parameters you could save (load) the measurement setup (e.g. the above) for the next run.
The search box helps to narrow down the parameters.
1640855226403.png

After loading the preset file you still need to

Tick "Group UDS requests" - by 7​
Click Log - Start​
Crank the engine - 3 seconds is enough.​
Stop logging etc.​
The logfile will be in folder C:\Ross-Tech\VCDS\Logs​
Please post the logfile.​
 

Attachments

  • eng_01_sync_A.u01.REMOVE.TXT
    132 bytes · Views: 13
Not another one of these is it;


Diagnose Dan where a VAG TDI engine would only start from cold after a very long crank. Turned out to be the variable valve timing actuator losing oil and retarding the cam to a point where it wouldn't start. I was surprised at the time that it wouldn't at least splutter and fire. Afterwards I wondered if that was a safety feature that the thing wouldn't start at cranking revs with a so far retarded cam. There was no error codes on that either, and Dan found it (we diagnosed it together! :grin bounce:) by the number of pulses from the crank reluctor between TDC and the cam at first crank, and when it finally started. That could explain the queer phase angle here ...
I think the clip is not exactly applicable to T6 diesel - ours is a more primitive one in :sick: this area.

Anyways, below a snippet from a Skoda engine on tick-over.

IDE00178Camshaft adjustment intake bank 1: specified value
10​
°
IDE00179Camshaft adjustment intake bank 1: actual value
10.06​
°
IDE00182Camshaft adaptation intake bank 1: phase position
-0.81​
°

The respective camshaft adjustment values on T6 diesel engines stay at 0.0 degrees always.
 
Thanks. I would expect that if we do not see injectors to start firing in 2-3 seconds any further cranking won't do it either.

Here is a slightly modified proposal for the next logging during the cranking. Now the prime suspect "IDE00182 Camshaft adaptation intake bank 1: phase position" is also included on this "short list.

Either tick the following manually or preferably use attached preformatted file as explained further down.
The file must have extension .U01 thus remove the extras from the file name.

IDE00021Engine RPM
IDE00182Camshaft adaptation intake bank 1: phase position
IDE00347Air mass: actual value:
IDE00351Main injection: start of activation
IDE00352Main injection: duration of activation
IDE00407Rail pressure regulation: status
IDE00416Starter control: terminal 50 feedback
IDE00589Fuel pressure
IDE07822Fuel pressure regulator valve: activation
IDE07824Tank-internal presupply pump 1 bank 1: activation
ENG113754-ENG113670P_L_Aps_synchronised_origin-Sync_origin
ENG113757P_L_Aps_timeout_detected

Once you have ticked the parameters you could save (load) the measurement setup (e.g. the above) for the next run.
The search box helps to narrow down the parameters.
View attachment 139958

After loading the preset file you still need to

Tick "Group UDS requests" - by 7​
Click Log - Start​
Crank the engine - 3 seconds is enough.​
Stop logging etc.​
The logfile will be in folder C:\Ross-Tech\VCDS\Logs​
Please post the logfile.​
Ahh this is brilliant Thanks again @mmi I'm away for a couple of days but will be sure to do this as soon as I'm back and I'll post ot straight up.

If I may ask you a question, I was speaking to an old school diesel mechanic the other day he was saying in some ford's the cam lobes are sweated on and generally when the timing goes in 1 of those the cam lobs can move.

Is the T6 the same in respect to the cam lobs being sweated on ?

Thanks again for your help
 
If I may ask you a question, I was speaking to an old school diesel mechanic the other day he was saying in some ford's the cam lobes are sweated on and generally when the timing goes in 1 of those the cam lobs can move.

Is the T6 the same in respect to the cam lobs being sweated on ?
I assume the cam lobes are sweated on also in T6 - just based on how camshafts are manufactured nowadays.

Anyways, I'm assuming it shouldn't be a the problem for the phase offset we are working on - because there is no mecahnical stress on sender wheel for Hall sensor which registeres intake camshaft position.

1640958199866.png
The full document available in T6Forum downloads


However, the exhaust camshaft is the one driven by the toothed cambelt. The intake camshaft is driven via spur gearing by the exhaust camshaft. As @catfood12 in post #46 mentions there is a possibility for a mistake in camshaft installation. However, for engine CXGB the OEM spare is a full preassembled module (below) which probably can't be disassembled.
1640958928163.png
Source: IFInterface

Ahh this is brilliant Thanks again @mmi I'm away for a couple of days but will be sure to do this as soon as I'm back and I'll post ot straight up.
Yes please - the setup records more parameters about crankshaft-camshaft sync process - I'm especially curious to see if there will be any "wobble" in phase offset during cranking.
 
Ahh this is brilliant Thanks again @mmi I'm away for a couple of days but will be sure to do this as soon as I'm back and I'll post ot straight up.
Please do a data logging with the new setup file and post the data.



Before (possibly) taking cambelt off perhaps you could try do the same recording when camshaft sensor (G40) is disconnected (inspired by this thread here)

I'd like to propose the following:

VCDS Preparations​

  1. Ignition ON
  2. Do full VCDS-Auto-Scan: VCDS > Auto-Scan > Start (on T6 VCDS detects all modules automatically, no need to select chassis) > Save
  3. Read engine faults codes: VCDS > Select > Engine > Fault Codes > Save Codes > Clear Codes > Save Codes
  4. Ignition OFF

Disconnect the camshaft position sensor (G40) connector​

It's located between injectors 2 and 3. According to repair manual should be enough just to loosen charge air cooler on top of camshaft module. Anyways, shouldn't take too long even if some more disassembly is required - the picture below was taken after 20 minutes of tear-down - although not by me :whistle:
Inked_CXFA-20171123_081952_LI.jpg
Cropped_CXFA-20171123_081952_LI.jpg
Please find T6 CXGB engine repair manual >here<

For disconnecting the sensor G40 - pages 384, then 389, etc.

VCDS Data logging​

  1. Ignition ON
  2. Read engine faults codes: VCDS > Select > Engine > Fault Codes > Save Codes > Clear Codes > Save Codes
  3. Start data logging (Adv. Meas.Values etc.) with the setup file - please do not forget to tick the "Group UDS Requests by 7" (greatly enhances sampling rate)
  4. Crank the engine - preferably at least 5 seconds.
  5. Stop the logging
  6. Read engine faults codes: VCDS > Select > Engine > Fault Codes > Save Codes
  7. Do full VCDS-Auto-Scan: VCDS > Auto-Scan > etc.

Good luck! I do really appreciate your efforts and sharing the logged data!
 
Has this been solved? I have exactly the same story and I need help. The fault has been sought for many days. Thanks guys.
 
Nice, if i disconnect camshaft sensor, engine will start so i quess camshaft module needs to be replaced.
 
  • Wow
Reactions: mmi
Nice, if i disconnect camshaft sensor, engine will start so i quess camshaft module needs to be replaced.
Did you do any of the proposed VCDS data logging (above)?
 
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