Non starting 03 Tdi130 Slightly confused!

[azonic1]

Hi folks.

Right this may end up being a little long-winded so I'll apologize now.

Tried to start the car on the first frosty morning last week. Everything normal as far as dash lights go. The engine turned over, 3 or 4 cylinders fired then went back to turning on the starter. Tried many times, no joy. The breakdown man came, lots of scratched heads, no fault codes.

Ok so the car goes off to the garage, apparently a dirty cam sensor was the culprit. Paid a modest fee for the service and the car was fine for a couple of days. Since then the fault has returned on cold starts and at the moment its a bit of a lottery as to whether it will start. 4 attempts for my girlfriend this evening with the car covered in snow at her work.

Now. You know that feeling when you've opened a can of worms.....

In the last week someone has told me that the Pd engines don't have a cam sensor. True?

I've also discovered a water leak through the front bulkhead somewhere around the harness connector box.

The car usually makes a 'squelching' noise when the ignition is first turned on, which I assumed was a fuel prime pump. This noise doesn't happen when the car fails to start first time. But I have been told that this is actually something to do with the ABS and that there is no prime/lift pump.

So I have formed a rough list of bits to check. Im looking for someone to tell me if they're a good shout or not.

Fuel filter change, not done for at least 50k (far too long I know)
Cam sensor change, if one exists
Ecu temp sensor, been told this could cause problems
Harness connector box, check for water in the electrics
EGR and anti shudder cleanup, never had them off so they are probably caked up and i've heard the anti shudder valve can stick shut.

Anything else you can think of? I've been told so many conflicting things this last week, my noodle is slightly baked

Thanks for reading, I hope someone can help.

Chris

 

[Seatmann]

Have a look at this bud, it's for a different car but it is a pd engine and might help.

http://www.myturbodiesel.com/1000q/a4/a4-pumpe-tdi-bew-index.htm

 

[lm_gauci]

Have a look at this bud, it's for a different car but it is a pd engine and might help.

http://www.myturbodiesel.com/1000q/a4/a4-pumpe-tdi-bew-index.htm

Looks like some good info in there, hopefully should help me out

 

[MJ]

That squelching noise could be the ASV opening, if this noise is not present when the vehicle won't start there's a good chance it's sticking in the closed position. Remove it, clean it up and try it or when you have it running disconnect the vacuum pipe going to it and see if it starts up the following day.

The 130 will have a lift pump in the tank which could also be the noise you speak of which, as already mentioned squirts fuel when the ignition is turned on so it primes the system ready for starting.

 

[azonic1]

Started first turn this morning, coldest of the winter so far -4

Have a look at this bud, it's for a different car but it is a pd engine and might help.

Excellent resource thanks a lot. Have bookmarked cause there's a number of other things on there i'd like to try out.

It would appear from the pictures that the pd engine does not in fact have a cam sensor. Can anyone clarify this before I go and verbally abuse an unsuspecting mechanic?

That squelching noise could be the ASV opening, if this noise is not present when the vehicle won't start there's a good chance it's sticking in the closed position. Remove it, clean it up and try it or when you have it running disconnect the vacuum pipe going to it and see if it starts up the following day.

The 130 will have a lift pump in the tank which could also be the noise you speak of which, as already mentioned squirts fuel when the ignition is turned on so it primes the system ready for starting.

The noise normally comes from under the drivers side of the car not from the engine bay. Could the lift pump be on the way out?

 

[Muttley]

azonic1 wrote

It would appear from the pictures that the pd engine does not in fact have a cam sensor. Can anyone clarify this before I go and verbally abuse an unsuspecting mechanic?

All PD engines have a sensor on the camshaft which tells the ECU which cylinder is ready to fire when starting the engine. There is a toothed hub underneath the camshaft belt drive sprocket which the sensor detects. The sensor uses the Hall effect, a non-contact electromagnetic means of proximity sensing, so I'm not sure how being dirty could affect it, unless there's a lot of metal chips in there.


The noise normally comes from under the drivers side of the car not from the engine bay. Could the lift pump be on the way out?


The fuel cooler is under the drivers side. A squelching sound may mean that you have air in the system. Certainly a change of fuel filter is the first thing you should do if it is well overdue.

There are two fuel pumps in the PD fuel delivery system, a lift pump in the fuel tank and a second pump on the cylinder head (the tandem pump, as the same unit also contains the vacuum pump) which circulates the fuel around the head and to the PD injector units. The lift pump starts up as soon as you turn the "ignition" on, the tandem pump is driven off the camshaft.

 

[darkhorse]

The noise normally comes from under the drivers side of the car not from the engine bay. Could the lift pump be on the way out?

That's the pump priming and I'd say it normal. If the fuel is below 2/3 a tank or it hasn't been started for a while it will make the squelching noise when the ignition is turned on. Otherwise you probably won't hear anything.

I'd definitely change the filter first, just for piece of mind. Check the battery next as the cold weather kills them. Then you could try unplugging the temp sensor and see if it starts.

Those are the easiest things to do, if you have no joy then start looking at the other things

 

[azonic1]

Thanks guys.

So no reason to go shouting at the mechanic then. Cool.

I've been wondering what that aluminium casting with the fins was for. As an aside would the removal of the fuel cooler cause any problems?

Can the power feed to the lift pump be accessed easily anywhere?

Off to try and source a fuel filter shortly. Let the fun begin...

 

[Muttley]

Don't remove the fuel cooler, it is very necessary. Excess fuel is recirculated from the head and injectors and is hot. It must be cooled to keep it within the operating limits of the injection system: hot fuel is less dense so you need to inject more of it. Without the cooler it could eventually get very hot indeed, especially if your tank was getting low.

The fuel tank is under the rear seats. Circular holes under the seat give you access to the fuel pump, fuel delivery/return pipes, fuel pump and gauge connections.

 

[azonic1]

Ok the fuel cooler thing was just an idea. We're moving to a farm in the new year and the road up to it isn't exactly smooth and the cooler looks quite vulnerable.

Well I changed the fuel filter yesterday. Ran up fine first time and drove no problems. Started this morning, again no problems.

My girlfriend just went to start it at work and nothing, exactly the same problem.

Going to check power to the lift pump if its still not starting when it gets back here.

Is the failure of the cam sensor the only thing that would stop the injection of fuel? Trying to narrow down the options.

 

[MJ]

the lift pump will make the noise until the system is primed, it will still pump after but the squelch will stop.