2010 Octavia 2.0TDI (BKD) not starting.

[pauldaf44]

Hi all. 

 

As I mentioned in my introduction thread earlier I purchased an ex health authority Octavia elegance estate at auction yesterday. I drove it home 95 miles with  no issues but when I got in it to go to work this morning it simply wouldn't start. 

 

It cranks over fine but just doesn't even attempt to fire up. I plugged in diagnostics and got a couple of codes 

One for Inlet manifold flap motor. (I thought this may have been the cause if it was stuck shut but it isn't it's stuck open so I can't see why that would stop it from starting.) 

Camshaft position sensor implausible signal. (This cleared and hasn't come back) 

 

RAC came to try and get it going unsuccessfully. He managed to get it to fire up using easystart but it would stall instantly again afterwards.

Plugged it in again and we have more codes.

Fuel pump relay open circuit.

All 4 glow plugs open circuit.

 

I have checked the fuses related to fuel pump and glow plugs and they are intact. But although the camshaft code hasn't come back live data stream does not give me a camshaft speed signal. RAC believes this is the fault so I have ordered a new camshaft position sensor but I am unsure this will work as I am not sure the live stream data would report when cranking anyway.

 

Any ideas.

 

Paul 

[J.R.]

A PD engine will fire with a U/S camshaft position sensor, it will lose its quick start feature but as long as the cranking speed is above a certain threshold it will fire, is yours a CR or PD engine?

 

There is something about the ECU having to see a certain cranking speed when cold but not hot (or maybe vice versa) which can be programmed out, that can cause non starting, cant recall the details.

[pauldaf44]

It's the 2.0tdi PD engine with BKD code. As far as I can tell it is getting no fuel, RAC mechanic thought the injectors simply would not fire as the ECU is receiving no single from the cam position sensor. 

 

[pauldaf44]

Still haven't been able to get this one to start. I have managed to get the all but the glow plugs codes cleared. I still have 4 fault codes, one for each glow plug and the car just turns over without attempting to fire. 

 I have given the battery a good charge off the car and it turns over at a decent speed. 

I have also swapped the fuel pump relay for a known good one and this has caused the fault code to clear. 

I intend to purchase a new glow control unit tomorrow in the hopes that this will get this starting. 

 

A quick question how reliant on the glow plugs is 2.0tdi (BKD pd engine) to start? Some diesels I have owned would start without glow plugs fairly easily and others you could crank all day and probably not start. It hasn't really come far above freezing today and I am not very familiar with this engine.

 

I am starting to regret getting rid of my 54 plate 210k passat 1.9tdi for this car.

[J.R.]

Mine is a 1.9 PD BKC engine and its completely tolerant of non functioning glowplugs, it was starting and running fine even in cold weather, as a new user of VCDS I did not believe that all 4 glowplugs could not be working and thought it must be a common wiring fault, I had never changed glowplugs in 500000kms on my MK1, it was starting on 1/4 of a turn how could all 4 glowplugs be faulty?

 

Wiser people on here convinced me and they were indeed duff, changed them for new and of course noticed no difference, it starts so well without them.

 

There is something on these engines about if it does not crank beyond a certain speed the injectors wont fire, looks like I am repeating myself 🙁 Failure of the cam sensor on the PD engine will not stop the engine from firing up, it will just lose the quick start feature and maybe have to crank a full 360° more, I would be looking at the crankshaft sensor and its wiring.

 

Can you get someone round with VCDS? That will tell you what the sensors are saying while cranking and if the injectors are being told to fire, could be a fuse problem or common wiring fault to the injectors, the multiplug on the end of the cylinder head can lose its little purple locking key and unwind, that would trigger injector fault codes and  create an open circuit on the injectors, dont think the cam sensor is wired through it.

[pauldaf44]

I don't know of anyone local with VCDS unfortunately. I have been using my IcarSoft cr Pro to read it using the manufacturer specific interface rather than the generic OBDII interface. Unfortunately my diagnostic system can't give live stream whilst cranking as it loses connectivity when the starter is running. If I were able to start the engine it would be possible to get live stream data as I can sync with the engine running but unfortunately not whilst cranking. I also fitted another battery and using a booster pack to assist has it cranking over pretty fast. 

 

Originally it had six fault codes stored in the ECU,

 

005659 Glow plug for cylinder 2 (Q11) Open circuit. 

Similar codes as above for Cyl 1, 3 and 4 

012547 Motor for Intake Manifold Flap (V157) Malfunction

005441 Fuel Pump Relay (J17), Open Circuit 

 

The later 2 codes have now sucessfully cleared and I have confirmed that a functional 449 relay is fitted in the fuel pump slot. Testing relays and cleaning electrical contacts also caused the V157 code to clear and not come back. 

 

There are also a number of other issues that may or may not be related. I have the left indicator and front fog light tell tales glowing dimly constantly whenever the ignition is on and the interior is wet. I think that when it was decomissioned as an ambulance they holes for the wiring for where the light bar and airials were have not been sealed up properly, as such when I got in it this morning there were water droplets on the interior light plastics and on the inside of the windscreen. 

 

[SuperbTWM]

Have you proved the fuel pump is working?

 

Its very easy to access under the back seat and you should hear it prime for 3 seconds when you turn the key.

 

Don't worry about the glow plugs, as @J.R. has mentioned these cars seem to start fine without them, even in sub zero temperatures. Its desirable to have them for emissions as they do glow post starting for quite a while in winter

Edited 19 January, 2020 by SuperbTWM

[Golf-Fiend]

Any chance it is an immobiliser problem? Do you have two key fobs? You tried both?

Just a thought.

[pauldaf44]

Tested the fuel pump and it is working with a strong prime as soon as you turn on the ignition. 

I have only one key so can't check with another, although from what I have read the immobiliser should allow it to start and then cut out 2 seconds later. 

 

 

[SuperbTWM]

Does the rev counter register the cranking speed?

[Agustnr]

This might sound stupid, but have you tried discharging the system? Unplug the battery for 30 mins and plug back, it might start.

My sister's subaru did that too and I let it discharge for about half an hour and then it worked again 

[pikpilot]

Just a wild guess from left field, but I heard of a Mk 1 with a similar issue that turned out to be a stuck anti-shudder flap.

 

 

[pauldaf44]

Update. She is still not starting and Is now with an auto electrician who has yet to find the fault. He says it is looking like an ECU fault caused by water ingress after a bad decommissioning job. 

[Guest]

How about using your nose, can you smell raw diesel from the exhaust pipe after cranking it with the accelerator fully depressed?

[J.R.]

When I once incorrectly set the cam timing (through relying on a neighbour to call out the TDC marking on the flywheel) and the engine showed no sign of starting I gave it a quick burst of Easistart, made a horrible racket but proved conclusively that it was not fuel starvation and hence must be injector timing.

[pauldaf44]

Progress update here. Still not starting! I gave up in the end and sent the car to an auto electrician who has had it for a month and still hasn't got her running. 

 

Fuel pump working as it should 

Glow plugs working

All engine sensors signalling correctly 

Immobiliser working correctly 

Injectors have all been load tested and are good. 

Timing has been checked all is as it should be it hasn't jumped a tooth. 

 

We are now looking at sending the engine ECU away for testing as it seems everything is now pointing towards that having failed internally. 

 

On the plus side he has managed to fix all the half on warning lights on the dashboard.

[Volf]

This sounds just like the problem I had with my 04 BKD after the first ECU went kaput (Water ingress and fried the board) I used https://www.cartechelectronics.com/ and they where most helpful. Managed to recover the custom map I had and installed it on to another ECU.
But after all that, still had running problems and it just wasn't the same after that. So I stripped the car down and binned the shell after endless troubleshooting and getting no where.

 

But whilst stripping it, I removed the fuse box tray from the engine bay and the huge connectors underneath it, had water in them. Not saying this is the problem, but it might not of helped things. No idea how long they had water in them for. But the problems you describe sound just like mine as before.
ECU okay - Glow plugs fine and the glow plug harness was replaced - New fuel pump to rule it out - Injectors had been tested - Timing hadn't changed.

Might be worth a check to see if they don't have water in them?

Hope you get it fixed.

[pauldaf44]

Well after a long wait she is now running again. I sent her to an auto electrician who ended up having to shut down due to lockdown but she is now running again. The fault was eventually traced to a break in the wiring loom between the engine bay fuse box and the engine ECU. Unfortunately the time sitting has done her no favours as she now has a major oil leak that wasn't there when laid up.  I should be able to pick her up next week after they finish sorting the other electrical gremlins like fitting a new stalk so the main beam headlights work.