Volkswagen Bora - Brain teaser.. 52 plate Bora 1.9 TDI wont start

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Wed 2 Nov 2011 09:07
Volkswagen Bora - Brain teaser.. 52 plate Bora 1.9 TDI wont start - m_loades
Where to start....

I have been working on the car in question for some time. It came to me as a non runner. 2 garages have had a look and found nothing. They demanded more money to keep looking and some just cant afford that.

When put on the diagnostics the car comes up with no faults.

When the car is cranked over, all readings on my mates snap on diagnostic seem correct.

We used a NOID to check the trigger signal to the injectors and all appear ok.

When the fuel feed or return to the tandem pump is removed fuel sprays out therefore lift pump is working and filter not blocked. Fuel is clean diesel too. No engine oil in it or veg oil present.

With the dreaded easi start hastily sprayed in to the inlet the engine will run but it is running on the easi start. As soon as this is removed the engine stops.

I think i'm getting close to the problem. Maybe very close (tandem pump??). I cant see it being all 4 injectors especially as there are no fault codes.

Thanks in advance to anyone that can shed a light!

Matt
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Wed 2 Nov 2011 14:35
Volkswagen Bora - Brain teaser.. 52 plate Bora 1.9 TDI wont start - mickeybo

engine code would help Regards Mickeybo

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Wed 2 Nov 2011 14:52
Volkswagen Bora - Brain teaser.. 52 plate Bora 1.9 TDI wont start - m_loades
Hi, its the ATD lump
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Wed 2 Nov 2011 17:09
Volkswagen Bora - Brain teaser.. 52 plate Bora 1.9 TDI wont start - m_loades

More invest...

I've just checked the timing. I was told it was correct but i had to make sure.

Just taken No1 injector out, blanked the port, turned on the ignition and the port filled with fuel so fuel is getting to the injectors. could the injectors be blocked?

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Wed 2 Nov 2011 23:16
Volkswagen Bora - Brain teaser.. 52 plate Bora 1.9 TDI wont start - VAG123

Any fault codes at all in any of the vehicle electrics?

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Wed 2 Nov 2011 23:34
Volkswagen Bora - Brain teaser.. 52 plate Bora 1.9 TDI wont start - bathtub tom

I had a Focus like that. It was the fuel pump munched itself. £1300.

Sorry!

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Thu 3 Nov 2011 08:55
Volkswagen Bora - Brain teaser.. 52 plate Bora 1.9 TDI wont start - injection doc

Worth checking that the injectors dont have a short in them ! this is a common fault and just pulls the ECU down.

You need to unplug the injectors and use an Ohm's meter on the two contacts to check for continuity, then check each contact to body ! if you have resistance then it has a short.

Sometimes they flag up as fuel pump relay fault when this happens.

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Thu 3 Nov 2011 10:03
Volkswagen Bora - Brain teaser.. 52 plate Bora 1.9 TDI wont start - Peter.N.

If fuel is definitly being injected and there is compression I can't think of anything else it can be but injection timing - assuming fuel is being injected when there is pressure in the cylinders.

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Tue 8 Nov 2011 07:59
Volkswagen Bora - Brain teaser.. 52 plate Bora 1.9 TDI wont start - m_loades
hi,

thank you all for your response.

i checked the resistance of the injectors and short to earth etc when i noid'd them. nothing wrong. no fault codes at all either.

i havnt carried out a full compression test due to lack of equipment but i managed to use my petrol engine compression tester to prove that its not shot. rough reading of 6-8 bar but it was only to check that valves were sealing etc. i know it should be alot higher than this.

i'm wondering if someone has put petrol in it. i'm sure i would be able to smell it but it is possible. any easy ways to check?

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Tue 8 Nov 2011 10:47
Volkswagen Bora - Brain teaser.. 52 plate Bora 1.9 TDI wont start - dieselnut

Assuming this is a PD engine.

Below is a link to an explanation of their AJM engine which should be similar.

It might just help to throw some light on the cause.

Best of luck.

http://volkswagen.msk.ru/engine/ajm/ajm_eng.pdf

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Tue 8 Nov 2011 14:46
Volkswagen Bora - Brain teaser.. 52 plate Bora 1.9 TDI wont start - madf

Test fuel pressure..

Sound sto me like a failed HP pump.

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Tue 8 Nov 2011 14:59
Volkswagen Bora - Brain teaser.. 52 plate Bora 1.9 TDI wont start - m_loades
Hi,

It is the PD engine so when you say hp pump you are relating to the tandem pump?? how do i test the pressure after that if its ported directly into the head?
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Wed 9 Nov 2011 10:50
Volkswagen Bora - Brain teaser.. 52 plate Bora 1.9 TDI wont start - dieselnut

There is no HP pump on this engine.

Some have a low pressure pump in the tank which you have indicated works ok.

Then you have a medium pressure tandem pump on the end of the camshaft.

If you look at page 20 from the link I provided above you will see a fuel pressure take off point from the tandem pump.

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Mon 14 Nov 2011 16:25
Volkswagen Bora - Brain teaser.. 52 plate Bora 1.9 TDI wont start - m_loades
*diesel nut*

i cannot read that link as its in russian or something??
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Mon 14 Nov 2011 16:32
Volkswagen Bora - Brain teaser.. 52 plate Bora 1.9 TDI wont start - injection doc

I would expect 380-420 psi compression which would be 27 bar approx.

using a petrol compression tester to test a diesel is a no no as its been done before and the gauges have been known to explode ! with a mechanic being carted off to Hospital with a compression tester embeded in their forhead !

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Tue 15 Nov 2011 14:12
Volkswagen Bora - Brain teaser.. 52 plate Bora 1.9 TDI wont start - dieselnut

When I click the link from this puter it takes me to the correct pdf in english, but from my laptop it takes me to the russian site as you say, they both show the same URL so I don't know where its going wrong.

Anyway, there is a pressure take-off thread with blocking nut that has to come out. There is a special pressure guage with threaded connexion V.A.S. 5187. The take-off point is bottom left near the fuel return line looking at the pump from the bulkhead.

Belive the pressure should be 7.5 Bar, there is a pressure regulator inside the tandem pump.

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Tue 15 Nov 2011 16:43
Volkswagen Bora - Brain teaser.. 52 plate Bora 1.9 TDI wont start - dieselnut

Just found this link, it's the same pdf document, hope this one works :-

http://www.myarchive.us/richc/VW_TDI_with_PumpeDuse.pdf

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Tue 15 Nov 2011 16:43
Volkswagen Bora - Brain teaser.. 52 plate Bora 1.9 TDI wont start - m_loades
Cheers for getting back to me,

Either tonight or tomorrow night i'm going to check that fuel pressure take off point (7.5bar) and the engine compression (380+psi). any other things you can think of while i'm there?

Regards, Matt
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Fri 24 Feb 2012 06:50
Volkswagen Bora - Brain teaser.. 52 plate Bora 1.9 TDI wont start - m_loades
Finally got round to working on this car again...

put a guage on the fuel supply line to the tandem pump and it read about 10psi (lift pump supplied with direct live)
removed guage and fitted it to tapping on tandem pump (pressure checking point) no pressure with pump supplied with direct live but getting about 15 psi during cranking. What should i be getting there?

disconnected fuel supply line and bridged it from my passat pd. i.e, bora now feeding from lift pump on passat (direct live) and therefore the diesel from passat. lots of cranking on bora... nothing :(

replaced tandem pump... nothing (passat fuel or bora)

carried out a compression test and all seems good :(

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Fri 24 Feb 2012 13:56
Volkswagen Bora - Brain teaser.. 52 plate Bora 1.9 TDI wont start - mss1tw

Could it be a faulty stop solenoid? Or a failed sensor that is still giving readings the ECU thinks is valid? Is the air intake clear?

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Fri 24 Feb 2012 14:08
Volkswagen Bora - Brain teaser.. 52 plate Bora 1.9 TDI wont start - m_loades
Thanks for the reply,

there isnt a stop solenoid on this car. not to my knowledge anyway

the intake is clear and it runs if i put fuel directly in the cylinder / use easy start

could be a sensor. bench tested the crank sensor and seems to work ok. cam sensor has been changed. i dont know any other sensor that would stop it from running
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Fri 24 Feb 2012 14:29
Volkswagen Bora - Brain teaser.. 52 plate Bora 1.9 TDI wont start - mss1tw

MAF sensor? Not sure if that would cause a non-start!

My limited understanding is that all modern diesels have a stop solenoid to refine the switching off of the engine.

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Tue 28 Feb 2012 09:07
Volkswagen Bora - Brain teaser.. 52 plate Bora 1.9 TDI wont start - m_loades
there is no stop solenoid on these cars. the injectors just have their signal taken away.

whilst we're on about the injectors.... all 4 dead! dodgy fuel to blame. from the sketchy history i know, the car lost power then died, a garage got it running so i reckon they knew it was the fuel, they probably cleaned it all out then filled it with clean fuel hence the clean fuel i found... 20 miles later though... small amount of dirt / fish batter or whatever foreign material has been introduced blocked them up. they now need recon or i need a new set.

I'll confirm this when its running! :)
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Tue 28 Feb 2012 11:40
Volkswagen Bora - Brain teaser.. 52 plate Bora 1.9 TDI wont start - dieselnut

I can't see that all 4 injectors would have failed together & you have checked that they all have a signal going to them.

There is an anti-shudder valve which closes off the air intake next to the EGR & would stop it running. They have been known to get stuck shut with gung from the EGR valve but as you have had it running on Easystart I can't see that being a possibility.

The pressure from the Tandem pump (15psi) doesn't seem to be correct. I understand that it should be around 7.5Bar which is just over 100psi.

Try posting your problem on vwaudiforum.co.uk there are a few knowledgeable posters on there who have worked on lots of these engines & may well be able to point you in the right direction.

Best of luck.

Edited by dieselnut on 28/02/2012 at 11:44

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Tue 28 Feb 2012 13:26
Volkswagen Bora - Brain teaser.. 52 plate Bora 1.9 TDI wont start - dieselnut

Forgot also to mention that I have seen reported that switching the light switch to side light has alowed a non-starting car to start.

I havn't got a clue why that should be, perhaps by-passes a failed relay or something, but worth a try.

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Tue 28 Feb 2012 13:47
Volkswagen Bora - Brain teaser.. 52 plate Bora 1.9 TDI wont start - Peter D

If this is a PD AWX engine then the minumum pressure at the test point on the Tandem pump is 3.5 bar. A non PD TDI has the same output pressure. Regards Peter

Edited by Peter D on 28/02/2012 at 13:54

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Mon 19 Mar 2012 08:06
Volkswagen Bora - Brain teaser.. 52 plate Bora 1.9 TDI wont start - m_loades
Fixed!!

4 x injectors!

didnt beleive it myself but changed them and 'wa-la'! Took an injector apart and it was siezed solid. Wouldnt recommend taking them apart either. lots of thin pins that snap if you dont hold it all inline whilst undoing. Mechanic at diesel diagnostics (coventry) thinks that someone has been running stripped red diesel. He has heard of the problem a few times, people dont care what they are putting in the fuel to get the colour out. its all about making a quick buck to them. he thinks they've been using some form of acid. either way, my pocket is noticeably lighter but it runs now :)

Thanks everyone for the help!!
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Mon 19 Mar 2012 13:10
Volkswagen Bora - Brain teaser.. 52 plate Bora 1.9 TDI wont start - dieselnut

Thanks for letting us know the outcome, how very unusual. Those Bosch injectors are usually ultra reliable but obviously wearn't keen on acid laced lubrication.

I guess it would have started running rough, then you got hold of it after it had failed completely

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Sun 29 Jul 2012 18:31
Volkswagen Bora - Brain teaser.. 52 plate Bora 1.9 TDI wont start - matt1086
That's brill I'm having a problem I have no power at all all seems good on vag no pressure leeks injectors set correctly timing set correct I've checked injector wiring nothing I'm thinking it could be injectors too what do ya think my engine is the bkc. Regards matt

Edited by matt1086 on 29/07/2012 at 18:37

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Tue 20 Mar 2012 11:33
Volkswagen Bora - Brain teaser.. 52 plate Bora 1.9 TDI wont start - Roly93

I had a Focus like that. It was the fuel pump munched itself. £1300.

Sorry!

This car doesn't have a HP fuel pump..

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Sun 18 May 2014 00:23
Volkswagen Bora - Brain teaser.. 52 plate Bora 1.9 TDI wont start - borarob

I am having the same problem engine code avs put and new pump in the tank and a new crack sencer in it ant the 109 relay can any 1 help pls

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