Won’t start. No fault codes

[teppo]

Nice, if i disconnect camshaft sensor, engine will start so i quess camshaft module needs to be replaced.

I couldn do it correctly. I have hex+can cable andwhile trying to "Tick "Group UDS requests" - by 7" it says i need new interface.
So i got only 1 time logging whivh didnt show anything.
Friend of mine loaned me v2 cable but i thing i got too litle time logged. Fuel pressure didnt rise enough. I quess that log wouldnt help.

I cant find any way to check intake camshaft timing. Cylinder pressure is good and same in all cylinders. Of course, measured in cold engine.

Timing belt has popped 2 tooth and i have changed belt, waterpump, high pressure pump, filter, diesel tank was drained and filled with new diesel and changed both speed sensors and pressure sensor. Injectors are tested and all works fine. Camshaft and rockers seems good and no error codes at all. Engine cranks, rail pipe pressure is about 350bar but doesnt run. cxgb engine, 150 000km driven.

 

[mmi]

I couldn do it correctly. I have hex+can cable andwhile trying to "Tick "Group UDS requests" - by 7" it says i need new interface.

The "Group UDS requests" just speeds up recording (better sampling rate) but obviously is a feature of the new cable.

So i got only 1 time logging whivh didnt show anything.
Friend of mine loaned me v2 cable but i thing i got too litle time logged. Fuel pressure didnt rise enough. I quess that log wouldnt help.

Hmmm... the log you posted shows there indeed was not enough fuel pressure (below 2000 kPa (20 bars) during cranking, should have been more than 25000 kPa (250 bars)).

And the engine didn't even try to inject fuel into cylinders so obviously no start.

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What does VCDS Advanced Measurement Value "IDE00182 Camshaft adaptation intake bank 1: phase position" show? - just ignition on, no need to crank the engine.

 

[Loz]

When you replaced the timing belt, did you time up the HP fuel pump?

 

[teppo]

When you replaced the timing belt, did you time up the HP fuel pump?

It couldnt be done without. crankcase, camshaft and pump are locked with special tool and then install belt and finally camshaft and pump sprocket locked.
Checked 4 times while trying to find problem.

 

[teppo]

The "Group UDS requests" just speeds up recording (better sampling rate) but obviously is a feature of the new cable.


Hmmm... the log you posted shows there indeed was not enough fuel pressure (below 2000 kPa (20 bars) during cranking, should have been more than 25000 kPa (250 bars)).

And the engine didn't even try to inject fuel into cylinders so obviously no start.

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What does VCDS Advanced Measurement Value "IDE00182 Camshaft adaptation intake bank 1: phase position" show? - just ignition on, no need to crank the engine.

i have checked pressure many times and normally at beginning its almost 400 and then goes to 350bar. I think this cranking time was too short and i have just installed injectors and bleeded system.
Now the car is outside carage and camshaft sensor unplugged so maybe next week i will work with this again and take new logs.

 

[Loz]

Have you tried a new camshaft sensor?

 

[teppo]

Have you tried a new camshaft sensor?

Of course. Also tried new and old crancshaft sensor and rail pressure sensor. Engine starts if i disconnect camshaft sensor but runs quite rough.

 

[Loz]

Of course. Also tried new and old crancshaft sensor and rail pressure sensor. Engine starts if i disconnect camshaft sensor but runs quite rough.

okay, just asking as you didn't say... I'll leave you to it..

 

[teppo]

The "Group UDS requests" just speeds up recording (better sampling rate) but obviously is a feature of the new cable.


Hmmm... the log you posted shows there indeed was not enough fuel pressure (below 2000 kPa (20 bars) during cranking, should have been more than 25000 kPa (250 bars)).

And the engine didn't even try to inject fuel into cylinders so obviously no start.

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What does VCDS Advanced Measurement Value "IDE00182 Camshaft adaptation intake bank 1: phase position" show? - just ignition on, no need to crank the engine.

I installed new camshaft module. 00182 shows 3.0 degree.
Now engine allmost starts but wouldnt stay on with all cylinders

old camshaf module was bad. timing was maybe 10-15 degree ahead for some reason.
pic shows old and new one, both locked same way.


heres log for this

 

[mmi]

I installed new camshaft module. 00182 shows 3.0 degree.

Should be ok - also it's stable in the log during cranking and engine firing

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Here's a snippet from the log:

• At 0.87 seconds from start of cranking ECU is happy with cranking speed & air mass & fuel pressure and thus fires the injectors (see IDE00351 Injection timing & IDE0035 Injection duration - GREEN).
• The engine starts to fire up at 1.10 seconds and gains speed well above pure cranking
• The air mass values are correct for the engine speed (normal idle approx. 11 grams/second)
• At 1.85 seconds ECU believes engine is starting to run normally and moves injection timing from "start" 0.5 degrees to more dynamic/early values (here -2.12, -2.64,... degrees)

So based on the data the engine indeed should run. But why it doesn't is a bit mystery. Probably something more "traditional" hardware related. Have you done compression test on the engine?

Just an observation - the fuel pressure build-up is very slow here - it takes 0.87 seconds from beginning of tha cranking to build up sufficient pressure. I would expect this to be less than 0.4 seconds. Anyways, it's not here the issue preventing engine to run.

 

[teppo]

Should be ok - also it's stable in the log during cranking and engine firing

Here's a snippet from the log:
View attachment 153165

• At 0.87 seconds from start of cranking ECU is happy with cranking speed & air mass & fuel pressure and thus fires the injectors (see IDE00351 Injection timing & IDE0035 Injection duration - GREEN).
• The engine starts to fire up at 1.10 seconds and as gains speed well above pure cranking
• The air mass values are correct for the engine speed (normal idle approx. 11 grams/second)
• At 1.85 seconds ECU believes engine is starting to run normally and moves injection timing from "start" 0.5 degrees to more dynamic/early values (here -2.12, -2.64,... degrees)

So based on the data the engine indeed should run. But why it doesn't is a bit mystery. Probably something more "traditional" hardware related. Have you done compression test on the engine?

Just an observation - the fuel pressure build-up is very slow here - it takes 0.87 seconds from beginning of tha cranking to build up sufficient pressure. I would expect this to be less than 0.4 seconds. Anyways, it's not here the issue preventing engine to run.

This is after i change camshaft module. I think pressure rises slow becouse this was third startup after assembly. Maybe stil some air in system. Before new module it wouldnt fire at all.
Maybe more bleeding tomorrow.
Yes, i have tested compression but not very accurate. I have only tester for petrol engines and I have to press meter to injector hole in camshaft module and results are more than 16 bar per cylinder but this is not accurate. I think this only shows valves and pistons are ok, no major problems.
Engine has new timing belt, high pressure pump, filters and diesel. Speed sensors and rail pressure sensor. Injectors are tested to be good. camshaft module and rockers are new.

 

[mmi]

Agreed, based on the indicated cylinder pressures nothing major in there - so possibly/hopefully just air in the system.
Good luck and please keep us posted

 

[teppo]

Agreed, based on the indicated cylinder pressures nothing major in there - so possibly/hopefully just air in the system.
Good luck and please keep us posted

This just wont run. Starts but shut immediately. cant be air anymore. takin camshaft sensor out only makes starting time much longer.

 

[mmi]

This just wont run. Starts but shut immediately. cant be air anymore. takin camshaft sensor out only makes starting time much longer.

Weird indeed.

You probably have run fuel lift pump VCDS output test when bleeding the system.

Start up fault

Really happy with the help so far - have never received any remotely useful input from the dealership. But in there defence they never observed it faulting first hand only my videos. VCDS has been fantastic so far - only my inexperience limiting it. Reading the comments on the time stamps does...

www.t6forum.com

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Let's grab full data package from engine and see if any clues are stored in there.

A) Record full engine data​

Please record and post two "blockmaps" from the engine

1) ignition on (engine not running) - before cranking​

2) after a failed start-up ignition still on​

How to:​

​

VCDS > Applications > Controller Channel Map >​

​

Tick/fill boxes as above and hit Go. ​

VCDS flashes screen for a minute (literally) - when finished hit "Done, Go Back") and there will be file blockmap-01-... in folder C:\Ross-Tech\VCDS\Logs\....​

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(B) Record engine start-up​

Record an engine start-up with the following ticked in VCDS Advanced Measuring Values,

IDE00021 Engine RPM​

IDE00182 Camshaft adaptation intake bank 1: phase position​

IDE00347 Air mass: actual value:​

IDE00351 Main injection: start of activation​

IDE00352 Main injection: duration of activation​

IDE00407 Rail pressure regulation: status​

IDE00416 Starter control: terminal 50 feedback​

IDE00589 Fuel pressure​

IDE03767 Engine status​

IDE05632 Fuel pressure regulator valve actual value​

IDE05633 Valve for fuel metering: feedback value measured​

IDE07742 Cylinder head: pressure sensor 3 bank 1: raw value​

​

NOTE: Instead of ticking the parameters one by one you could use the attached preset file for the above (Load...) (Remove the PDF-extension to make the file .u01-file).​

​

​

Tick "Group UDS requests" - by 7 (speeds up the recording significantly)
Click Log - Start
Crank/start the engine
Stop logging etc.
The logfile will be in folder ...VCDS\Logs

(C) Record full engine data​

As mentioned in (A) - after the failed start recording above. Please keep ignition on through (A)-(C)

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Well, hopefully there will be some clues - because based on the earlier recording it seems that actually the injectors stopped injecting fuel.

As you can see the injection duration (GREEN box) is active = little fluctuation of the values.
However, on this ECU the consecutive same values (here 943 us) actually indicate that injectors are closed thus no fuel into cylinders. The same is true with injection timing (here -3.34 degrees)

Just remains the mystery why....

 

[teppo]

Weird indeed.

Everything bleeded many times. I think, first it runs with just one cylinder for short time. After meny startups and bleeding I got two cylinder and engine stays on. After few minutes running and litle driving, i'm quite sure i got 3 injectors working now. MAybe air is blocking injectors and of course, after injectors was tested to be good, lots of starting and removal/installation done.

 

[mmi]

Everything bleeded many times. I think, first it runs with just one cylinder for short time. After meny startups and bleeding I got two cylinder and engine stays on. After few minutes running and litle driving, i'm quite sure i got 3 injectors working now. MAybe air is blocking injectors and of course, after injectors was tested to be good, lots of starting and removal/installation done.

Indeed exciting Easter job! Thanks for sharing
And, yes, those Cylinder 1-4 internal moment values should be relatively close to each others.

 

[teppo]

Becouse 2 and 4 is negative sometimes i believe thjose cylinders didnt get any fuel. Friens says that tehse delphi injectors may stuck quite easily and needs lot of rpm and driving to get them back to work.

I dont know which caused this problems but ignition belt has jumped few tooths and exhaus camshafts sprocket wasnt in its correct position. So renewing camshaft module, rockers and camshaft belt was necessary.

 

[mmi]

Becouse 2 and 4 is negative sometimes i believe thjose cylinders didnt get any fuel.

That's interesting. Just checked an old log file of a perfectly running engine. Indeed there are also negative values - obviously need try identify under what conditions it happens. Engine braking perhaps

 

[teppo]

All good on T6 back on road again. Main issue was bac camshaft module and belt. After all is changed and working, still need to run engine about 1 hour to get all injectors bleeded. Of course fuel pump bleeding 20 times first.

 

[Kaph]

Hi, could you look at This video and tell me if your car was like This When you tried to bleed the injectors?
Have had the fuel rail and pipes out on mine and cant Get it to run..