VW Golf 2.0 BKD non Starter

[zimcenkorazvan]

Hi guys, new member here, long time follower.
Thank you for having me on this forum. I really need help getting my car back on the road.
So about a month ago my workhorse which I own for 13 years , VW golf MK5 with BKD engine decided not to start one morning. It was running fine the night before when I arrived at home. Actually it gave a sign a day before when it didn't start at first crank as it used to. That day I had to crank it a 2nd time while it seemed unusual. Now it's dead for more than a month.
Things I've done so far, after searching all the possibilities on this forum.
1. Obviously the first thing was to connect my Delphi diagnostic tool which I use since I have the car, 13, years. No fault codes.
2. Replaced the crankshaft sensor since I read it may not give fault codes, however was registering the cranking speed, about 190-230 RPM. If I disconnect the cam sensor it throws an error, so I assume the cam sensor works, amd I understand the engine should start with it disconnected.
3. Replaced the starter as I understand the ECU needs to see a higher cranking rpm, not it cranks with 320rpm.
3.checked in tank pump flow, about 2.6-3 litres per minute after the fuel filter.
4. Replaced fuel filter just in case.
5. Replaced the tandem pump, just in case.
6. Fitted temporary clear fuel pipes tonand from tandem pump to observe the bleeding of the tandem pump, it is perfectly primed, no air bubbles.
After all this, moved my attention to the electrical side since I know the fueling is all good.
7. Checked all the fuses on the side if the dash and engine bay.
8. Checked/tested all the relays under dash and one at engine bay.
9. All the lights on the dash kit up and go off as they should, ex glow plug light and immobilizer light, both light up for a short wile then switch off.
10. Removed valve cover, checked each wire in the injector loom for continuity and short to ground, all good.
11. Visually cheched a large oart if the wires around the engine in the main loom, they are all preserved very well and clean. It seems my car has a very tidy electrical system, well protected but I may he wrong.
12. Tried to start the engine with one injector disconnected at a time. No luck.
13. Forgot to mention, the timing is ok visually, and the engine starts on eazystart, only as long as I spray it.
Now.... Something I should have checked and spotted from the beginning ...
Live data I can read the temperature from all the sensors, when I look at the injectors fuel quantity correction it reads 0.0 on all cylinders.
Injection valve status reads 128 on all four of them. I assume it's the injectors..
I cranked the engin with the injectir loom disconnected, and no fault codes - is this normal?
Then I looked more careful in the diagnosis live data, and I read CAN: communication electronic central unit : No Value.
The CAN communication with all the other systems (abs, instrument panel, immobilizer, steering etc) shows status : OK.
Does this seem like a fried ECU since it's the only part the CAN doesn't communicate with?
Thank you very much for reading such a long post.

[Crasher]

I can’t see a lack of comms between the engine and body control module being a problem and if it was the immobiliser it would start and cut. Have you given it a whiff of brake cleaner? The cranking rpm was low and is now excellent.

[mickeybo]

At ignition on you should get voltage 12vs at ecu no a3-a5 - a6 if none found reply back

[zimcenkorazvan]

Thank you for replying Crasher!
Actually I was hoping you would reply, I've seen you helped everyone to find out their car's problems .
I've tried ezystart after the tandem pump change, numerous times, no luck. I've fitted temporary clear pipes so I an see te pump priming, it's definitely 100% primed. I've replaced before the tandem pump and indeed is a little difficult tonstart the engine afterwards.
I've ordered a tested ECU, one of those remaped from ebay, with Immo disabled, at least I would be sure the immo is not in fault, I've read thet it can sometimes behave unusual and xar doesn't syart at all. Maybe it is not tue but at least I excluded another.
I will post back on Thursday when the ecu arrives.
Thank you again!

[zimcenkorazvan]

At ignition on you should get voltage 12vs at ecu no a3-a5 - a6 if none found reply back

Thank you Mikeybo!
Unfortunately I didn't have the schematic yesterday when I removed the ecu, I will have to wait for this until Thursday as I will be away for 3 days.
I will definitely check and report back.
To be honest I hope is the ecu, it would be much easier that to take apart the whole electric
If no 12v on those pins from the T94 plug is present, where to look next ?
I've seen some awkward resisor or fuse on the red cables IMG_20250516_122622_HDR.jpggoing to the ecu, close to the T94 plug, any idea what they are ?

[zimcenkorazvan]

At ignition on you should get voltage 12vs at ecu no a3-a5 - a6 if none found reply back

Hi Mikeybo!
I couldn't resist today before going away and tested the power on the pins you mentioned.
NO 12V power on any of them. Ignition On, ecu removed, measured directly between the pins of the plug and battery .
Any idea where to look next for the missing voltage supply ?
Thank you very much!

[Crasher]

So even using Easy Start it will not fire up? When you crank it over, so it pulse or just spin over with a flat note?

[zimcenkorazvan]

So even using Easy Start it will not fire up? When you crank it over, so it pulse or just spin over with a flat note?

Apologies, I may have not been very accurate in my explanation.
The engine starts on Ezystart, but will only stay running for as log.as I spray it.

I replied back to Mikey above, I measured today morning befor I left and there is no 12V at pin 3,5,6 on he ecu plug, the T94.