temperemental starting?

gtiboy

gtiboy

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Hi
I am a bit miffed i have a Audi a6 avant quattro sport 2.5tdi.
Woke up this morning stared fine, did a few jobs and then went to start the car and hey presto it wouldnt start.
Went back to it 2 minutes later and boom it fires up ?
All lights and dashboard lit up fine and engine turned over but no awakening of the actual engine?
Also this morning sometimes it starts first time and then dies however then fires up first time ?
any ideas?
thanks in advance
 
Damp?
Injectors?
Injection Pump (ouch)?
Timing (Pump/Cambelt ouch)?
Ignition Switch?
Corroded Terminal (battery and distribution board)?
Glow Plugs?
ECU (can also get damp)?
Immobiliser?
Oh and change key battery ....mad but works on TT's

Forgot...check for bubbles in the fuel line...

Shove a can of diesel conditioner through with 1/2 tank of Super Diesel.
If that fails check timing with Vag Com.
 
some one just said the uplift fuel pump in the rear could be the cause ?
I will change the batteries tomorrow and timing belt has been done about 10000 miles ago so ?
I only use shell v power but will put the diesel conditioner i tomorrow just for peace of mind also.
I have done 300-400 miles this week and it has run perfectly with no issues just this starting problem .
 
If your getting air bubbles in the delivery line they could be right. The tank pump is however really only there to clear the baffle plate. The injection pump does the work.
The fuel lines go hard and can loose their seal and let air in (any leaks?)
The fuel filter and the valve on top of it are also issues.
 
Update time !
Got it scanned yesterday and surprise surprise not fault codes!
I have ordered a fuel filter bleed valve and a new fuel filter just as a precautionary measure so lets see when i put these on today ?
Will get back to you once done.
On a better not found a spare key for the car under the back seat so now have all three keys, result !
 
Update time !
genuine fuel filter and fuel bleed valve have gone on and the car runs more better and is a lot more responsive ?
The fuel filter looked brand new so no ideas there ?
Dropped the oil and filtersall round while we were at it so lets see?
I think its the bleed valve because it looked battered probably on from new .
 
and the dreaded problem has returned .
will try and get the car scanned this week ?
any body in or around leeds with the magical tool ?????
 
just got it scnned and its flashed up three codes


01376
17978
00550
on the printout it says control module part number 4B2 907 401 E
is tis the pump or the ECU at the top of the pump ?
This is getting more confusing by the minute phoned a few people and one says ECU the others say pump ?
dont want to get stung personally
 
4B2 907 401 E is the main ECU and as such will appear on a scan.


You seem to have OBD codes not a Vag Com scan..

01376 Thats an engine mount solenoid... no effect on starting....need a new mount
17978 Thats an immoboliser error ...thats a starting fault and could be the pump
00550 Start of Injection Regulation: Control Difference thats an injection pump fault IMHO

If your in the UK you could send the pump to ECU Testing (abour £40 to check, repair around £100 ish) you have to dewire it from the pump. Instructions if you need them on request.

Diesel Pumps - Bosch Diesel Pump

Or you could send the pump to Diesel Bob

Diesel Bob Tuning - Home

Inspect around £75 and fixes from £350 to £650 for an as new Bosch verified exchange with 12 months warranty.

New pump will also need the Immoboliser reprogramming about £45 by a car locksmith

Either way this is not a cheap or simple fix....

I am not an expert so wait for a second opinion.....just been here...
 
The final word on this is that the EDC on the fuel pump was goosed .
My mechanic has sent it away for checking and it was diagnosed to be faulty so hope to be on the road when it is back .
Thanks for all your help and advice once again .
Will update as soon as its on the road .
Quite a common problem apparently ?
 
Its right up there with DSG gearbox mechatronics, abs ECU's and TT Dashpods!

Glad you on the good road now!
 
audi upgrades
I hope so too TYphoon !
thanks for all the advice .
i personally wont believe it till im driving it ?
 
Sorry guys problem still there !

VCDS codes are now


01376-engine speed sigal for injecton pump
37-10-faulty intermittent

17978-engine start blocked by immobilizer
p15070-35-10- - intermittent

00550-start of injection regulation
27-10-implausable signal-intermittent

Help please !
 
Do you run on biodiesel?

[h=2]00550 - Start of Injection Regulation[/h][h=3]00550 - Start of Injection Regulation: Control Difference[/h][h=4]Possible Symptoms[/h]
  • Malfunction Indicator Light (MIL) ON
  • Loss of Power
  • Starting Problems
  • Transmission in Emergency Mode
[h=4]Possible Causes[/h]
  • Fuel Tank incorrectly filled with Petrol or Biodiesel
  • Air/Water in Fuel System
  • Injection Timing incorrect
  • Electrical Fuel Pump faulty
[h=4]Possible Solutions[/h]
  • Check Fuel Tank for Petrol and Biodiesel
    • Drain Tank and Fuel System
  • Check Fuel System for Air/Water
  • Check Fuel Supply and Return Lines for Blockage and Leaks
  • Check Electrical Fuel Pump
  • Check/Correct Injection Timing
    • Perform Basic Setting / Use TDI-Graph






 
I only use shell V power mate nothing else .
 
I had those......recon pump.....hope its not the same for you...
 
looking that way pal (typhoon GB)?
what are we looking at price wise ?(pm me if u dont want to go public )
 
The edc pump is gone mate, I would send the pump to diesel bob for rebuild. As you been advised above make sure the specialist know how to time it properly. Can be done with the bumper on the car, replace the tensioner with a genuine Audi part, had a few snapping the bolt and timing jumps as the belt gets slack.
 
See post 10. Add about £300 for the belts etc. Course this is DIY.
My whole pump journey is on A world for detailers... search A6 Avant Refurb....
Independent is going to add around a grand to that for labour.
As adamss24 said not replacing tensioner and I suggest the belts etc is false economy.
 
Thanks guys for the info and advice much appreciated !
 
If you do look at DIY drop us a PM and I will loan the timing keys and pins.
 
TYphoon GB said:
If you do look at DIY drop us a PM and I will loan the timing keys and pins.
Click to expand...
Thanks for the offer but thats well beyond me if im honest .
Thank for the offer though much appreciated pal !
 
I found i had the dreaded plenum chamber flooding problem the other week so the last week i have been drying out the car and cleaned and removed the fantastic grommets !
I started the car after drying out the ecu and also the gearbox ecu whic were quite damp and had moisture in the boxs and carpets and the car started first time and remained running for up to two hours with the air con on? i have started it and left it running for at least 3-4 hours since saturday with no isuues
It did not hestitate once and also started on the key first time everytime?
This leads me to believe it was possibly a damp issue ?
Will get the car fault read again tomorrow hopefully but is this a possibility ?
 
Sorry to bring an old post up, but i believe an update once started should be completed and updated so that it can possibly help someone in the future.

Well the pump was sent to diesel bob and has returned fully refurbished to as new .
Thanks to adams24 and typhoon for the advice and also anyone else who contributed.
I am now just waiting for the main man to come and install and time the pump !(friday)
Will post more on friday whe done thanks
 
New diesel pump was fitted today and timed by the legend that is Adams24 .
Thanks Chris for all the input pal.

If your struggling with a 2.5 tdi he's your man
 
Any ideas what it is I get random power loss on hard acceleration any help would be appreciated
 
Is the loss of power when its under load eg; going up a steady incline?
have you had the car scanned for faults ?
 
Extremley small bubbles are normal i have them but not large ones like half a pea size ?
Have you changed your fuel filter (read up about it before as it not simply a unplug and plug method)
Or the black fuel valve on top of the filter ?
 
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