Volkswagen Passat B5 2002 VW V6 TDI - Cutting out when re started

[4matt1]

Hi Can anyone help. I have seen similar posts, but dont think they are exactly the same issue. About 3 months ago, my 2002 V6 Tdi just stoped when I went to go out again. The car had been driven fine all morning, but came home for some lunch. Started it after lunch, drove down the road about 100 yards and it just cut out. Left it for about 2 hours and it started and ran fine after that. A week later, it did exactly the same thing. Lent it to my VW mechanic, mate of mine and he had it for a month, driving to and from work, no problem and he could not find any fault codes, when he came to pick it up.

He obviously didnt drive the car during the day, so it did not replicate the fault, because he wasnt getting back into it soon after stopping. IE he was driving to work and then driving home in the evening, which gave it time to cool down. Got it back, drove it for a few days. Parked in a car park, went off for about half an hour, came back, drove about 100 yards and it packed up. AA came, it started, but then stopped immediately, fault code for Engine speed crank shaft sensor. Took it to my VW mate, new sensor the next day, drove it for a week. Parked in a car park, came back about 45 minutes later. Started it up and then it cut out.
Part of me wants to just get rid of it, but it is in stunning condition and would like to keep it, if we can just solve what the problem is.
Given the code was for the crank speed sensor, I cant help thinking that it is still related to this, but the fault must be somewhere else within the crank speed sensors circuit, IE the ECU or the wiring....

So to sum it up: I still cant help wondering, why this only happens after the car has run for about an hour and been left for half an hour or so. It never happens during a journey, only when re started and then within the first couple of minutes of re starting.


Any ideas?

[Crasher]

I would replace the ECU power relay (in the box under the windscreen with the ECU) first and if that did not help, chnage the crank speed sensor. Neither of these tend to leave a fault code when they fail.

[4matt1]

Hi again. We have replaced both the ECU power relay and the crank speed sensor. Still got the same problem. Did get another fault code before replacing the ECU relay. 01259 Fuel pump relay - short circuit to ground or open circuit - Permanent. Also 01376 Engine speed signal, injection pump - faulty - intermittent.
Still same old sequence. Never a problem starting from cold. Run for 20 to 25 mins, then leave it for 40 mins to 1 hr and generally wont start. Then leave for yet another hr or so and it will start. Do you have any other thoughts or suggestions. Many thanks Matt

[niall campbell]

guess you need to check wiring to from fuel pump and injection pump/ governor

does the injection pump have a solenoid to switch off fuel ? I would guess it has and so check wiring and connection onto it, with the possibility of replacing the solenoid switch

[niall campbell]

Please Help A4 2.5 TDI wont Start - Fuel Injector Pump? (http://www.vwaudiforum.co.uk/forum/showthread.php/93142-A4-2-5-TDI-wont-Start-Fuel-Injector-Pump) theres also this old post

[4matt1]

Many thanks Niall... Something else to work on. I feel sure that it is in the areas you mention. Just cant help thinking that the fact it only happens on re start, when warm, but left for about an hour, must have a clue as to what it is.

[Crasher]

The fuel pump relay is for the in tank pump, this only brings fuel into the swirl pot, the injection pump then draws the fuel from the pot so with a decent amount of fuel in, the fuel pump not working won’t prevent it starting. The engine speed signal failure WILL stop the engine and means a new or rebuilt pump, it is not a normally replaceable component.

[4matt1]

OK Thank you Crasher. I have had to replace a main injection fuel pump on a previous car. Costly game. Are you saing it is the main pump, not the tank lift pump.

[Crasher]

Yes the VEP (Verteiler Einspritz Pumpe), the engine speed signal for the ECU comes from the pump.

[4matt1]

OK Thanks again. Am I correct in believing it is the electrical componant that fails on the soldering on the motherboard. Do I actually need to replace the entire unit, or would this work, that I found on ebay, component is in Germany and all in German.
STEUERGERÄT EINSPRITZPUMPE BOSCH VP44 AUDI VW 0470506006 059130106B 059130106BX

[Crasher]

You could try but we always fit a Bosch exchange unit as we can't stand having failures that come back under warranty. You can imagine if we fitted that part and charged accordingly and then something else went wrong in the pump that wasn't related, the **** I would get from the average customer just makes it a bad idea.

[4matt1]

OK Agreed. I have read many posts on the subject during the evening and anything other than a refurb or new unit would appear to be a false economy. I even have the pump that was fitted to my previous V6 TDI but the part number is 1 digit out. IE it is 0470 50 60 02 but the part number on the one that is playing up is 0470 50 60 06, so probably wont work and has been off that car for about 3 years, so it may not be suitable if parts have become dry, that should not. I don't mind spending £600 on a refurb pump and paying my VW mate to remove/fit, if it really will solve the problem, just wish there was a way of truly knowing.

[Crasher]

Well the VW explanation of the fault code for the sensor says "replace pump" and that's it...

[4matt1]

OK Many thanks. Replace the pump it is then.