Technical Fiat Ducato 2.3 not started

[reni]

Hello! I have a problem with a fiat ducato 2.3 multijet engine, year of manufacture 2008. It turned off suddenly and did not start again. The fuel pressure sensor is faulty, I replaced it with a new one but still the same problem, the car won't start. I have noticed that the tank pump only works for a few seconds, the moment the engine starts, the pump does not work. We have made some measurements and very little energy goes into the sensors. Your advice would be of great value to me

 

[bugsymike]

Hello! I have a problem with a fiat ducato 2.3 multijet engine, year of manufacture 2008. It turned off suddenly and did not start again. The fuel pressure sensor is faulty, I replaced it with a new one but still the same problem, the car won't start. I have noticed that the tank pump only works for a few seconds, the moment the engine starts, the pump does not work. We have made some measurements and very little energy goes into the sensors. Your advice would be of great value to me

Someone may correct me, but I believe once primed by the low pressure pump in the fuel tank , the high pressure pump will draw the fuel as it needs.
I actually had an 03 Doblo 1.9 non turbo that didn't have a tank pump fitted at all. It had a different fault which I was able to test for by running a can of fuel on the wing with the high pressure pump sucking it directly. The fault it proved was an air leak on the plastic connection of the flow and return fuel pipes. Not relevant in your case.
If not already done, I would advise a "leak off test" at the injectors on your engine to measure if any injector leaks too much in to the leak off return to the fuel tank. This is done by connecting four plastic bottles, one to each return from the injectors so you can measure exactly how much is "leaking " past each injector pintle body.
It only wants one dodgy injector to leak too much and it shuts the whole engine down on a common rail design, unlike the old days where it was possible for one injector pipe to be hanging off and the engine could still run ( badly) on three cylinders.
This maybe the reason you have no/low line pressure reading rather than a dodgy sensor.

 

[steve clark]

Someone may correct me, but I believe once primed by the low pressure pump in the fuel tank , the high pressure pump will draw the fuel as it needs.
I actually had an 03 Doblo 1.9 non turbo that didn't have a tank pump fitted at all. It had a different fault which I was able to test for by running a can of fuel on the wing with the high pressure pump sucking it directly. The fault it proved was an air leak on the plastic connection of the flow and return fuel pipes. Not relevant in your case.
If not already done, I would advise a "leak off test" at the injectors on your engine to measure if any injector leaks too much in to the leak off return to the fuel tank. This is done by connecting four plastic bottles, one to each return from the injectors so you can measure exactly how much is "leaking " past each injector pintle body.
It only wants one dodgy injector to leak too much and it shuts the whole engine down on a common rail design, unlike the old days where it was possible for one injector pipe to be hanging off and the engine could still run ( badly) on three cylinders.
This maybe the reason you have no/low line pressure reading rather than a dodgy sensor.

 

[steve clark]

Just a thought derived from experience with my car which once ran out of fuel because of a faulty fuel gauge, and would not start...

The car (not a FIAT) has an electric lift pump which is meant to move fuel up to the common rail injector system which is mounted on the engine, some way above the fuel tank, therefore the system needs to be primed if air gets into the lift system e.g. via air leaks on the suction side (or running out of fuel).

Priming simply consists of making sure the tank has several litres of fuel minimum, then turning on the ignition (this lifts fuel from the tank - you might hear the pump running, but it shuts off automatically to prevent damage to the mechanism) for about 10-15 seconds, then turning off the ignition for 20-seconds or so, the on again for 10-15 seconds, then off for 20 seconds, and repeat several times. If the priming works it will eventually fill the common rail system and the engine should fire

Let me know if this works...

Steve

 

[bugsymike]

Just a thought derived from experience with my car which once ran out of fuel because of a faulty fuel gauge, and would not start...

The car (not a FIAT) has an electric lift pump which is meant to move fuel up to the common rail injector system which is mounted on the engine, some way above the fuel tank, therefore the system needs to be primed if air gets into the lift system e.g. via air leaks on the suction side (or running out of fuel).

Priming simply consists of making sure the tank has several litres of fuel minimum, then turning on the ignition (this lifts fuel from the tank - you might hear the pump running, but it shuts off automatically to prevent damage to the mechanism) for about 10-15 seconds, then turning off the ignition for 20-seconds or so, the on again for 10-15 seconds, then off for 20 seconds, and repeat several times. If the priming works it will eventually fill the common rail system and the engine should fire

Let me know if this works...

Steve

If you have just ran out of fuel or changed a fuel filter, what you mentions certainly works on most vehicles if that is the only issue, although recently I serviced my daughters VW Tiguan and due to the setup it prevents that self bleed action all together. I believe with the right diagnostic tool it is possible to activate the fuel pump in the tank, but in the absence of that it involved filling the filter with diesel, sucking fuel through the return system, along with the ignition on , off priming method you mentioned. Having changed many fuel filters in the motor trade in fifty years , this was the most trouble, so you can imagine the stick I was getting from my daughter who had just bought the vehicle.
I may be wrong but I don't think that is the problem at the start of this thread however.