Elektroda.com
Elektroda.com
X

Search our partners

Find the latest content on electronic components. Datasheets.com
Elektroda.com

Ducato 3.0 - low fuel pressure - Low fuel pressure on the rail.

rogale2 13728 18
This content has been translated flag-pl » flag-en View the original version here.
  • #1
    rogale2
    Level 9  
    Hello, I have a problem with my Ducato 3.0 2009 ~ 450,000km.

    The car worked well throughout its life, all filters and fluids were replaced on time, refueled only at Orlen.
    I did not feel a drop in power despite this course.

    At the end of that year, error P0091 started to appear sporadically. The car entered emergency mode. I drove about 10,000 km like this. The error once occurred several times a day, sometimes for a week it did not occur at all.
    Then, after replacing all the filters, the car started to enter emergency mode every time I accelerate strongly and I have about 2200-2500 revolutions.
    After connecting the Multi Ecu Scan (this is my program for my ducato) and browsing the parameters while driving, I noticed that during acceleration there was a difference between the expected fuel pressure on the rail and the real one. At the expected 1600 bar, it was 1300 bar and when the difference became large enough, the car went into emergency mode or less often it went out completely.

    I drove 2000 km because I had to and I decided to replace the fuel filter again and measure the pressure of the pump in the tank.
    My pump in the tank is clearly audible and I suspected that it might be giving too little pressure.
    We blinded the exit from the fuel filter with a pressure gauge which showed its maximum value of 7bar, so the pressure with the blind pump is higher. Probably the measurement was done wrong, we should plug the pressure gauge into the system and see the pressure during firing. I didn't know it then.

    After this exchange and measurement, the car stopped starting. During firing, the pressure on the rail is 80-100 bar, while the expected ~ 300bar. It also does not fire on the cake. We managed to fire when we connected the mother (battery support device) and the starter was spinning like crazy. However, the car went out even when a little gas was pressed while stationary (P0091 or P0092). After unscrewing the bolt during injection and turning, no fuel flows.

    I probably have a cp1 pump, only a pressure sensor on the rail and a fuel regulator on the cr pump (probably called a dump valve, mounted on 3 torxes).
    I thought that this valve could send all the fuel back to the tank and that is why the CR pump has too little pressure to start. So I plugged the return fuel hose and the car fired (after a while it went out because of too high fuel pressure, which is normal). I replaced this regulator with a new one, but it did not help. The car still does not start, the pressure when firing is 80bar. Interestingly, during the launch, the valve on the pump is about 40% open, I don't know anything about it, but it's a bit strange for me.



    I present two videos of the parameters during launch:
    https://youtu.be/llpx39O31zw

    Firing up during a blind return to the fuel tank:
    https://youtu.be/YIfq3gQcNfY

    I wonder what to do next. It would be wise to regenerate the CR pump, all injections, replace the sensor on the rail and the pump in the tank, but these are huge costs. I'd rather be diagnosed with this one particular cause.

    What do you advise to do?
    Should an adaptation of the pressure regulator be done after replacement? I don't see an adaptation option in Multi Ecu Scan.
    It is worth measuring the pressure behind the filter correctly by plugging into the system to know what pressure the cr pump gets?
    Is it worth connecting an external fuel pump to exclude damage to the pump in the tank?

    Is opening the valve to 40% during start-upis normal? from my reasoning it follows that if the opening was minimal, the car would start (it fires when blinded). Maybe it's a problem with controlling the regulator?

    Or maybe the pump in the tank should be so strong that despite opening to 40%, the CR pump should get these, for example, 3 bars and fire?

    Or maybe the cr pump just fell? Why then it fires during blindness and even gives too much pressure.

    Thanks for all the advice.
  • #2
    szymitsu21
    Moderator of Cars
    Detach the ankle from the pressure regulator and see how much pressure it will build up.
  • #3
    rogale2
    Level 9  
    When the regulator cube is unfastened, the pump in the tank does not start.
    Fuel Pump Relay to OFF non-stop.

    Pressure below 10 bar
  • #4
    jenusz11
    Level 20  
    check carefully best try to bypass the pressure regulator to the ecu
  • #5
    szymitsu21
    Moderator of Cars
    rogale2 wrote:
    When the regulator cube is unfastened, the pump in the tank does not start.
    Fuel Pump Relay to OFF non-stop.

    Pressure below 10 bar


    and still, it should be much bigger.
  • #6
    rogale2
    Level 9  
    szymitsu21 wrote:
    rogale2 wrote:
    When the regulator cube is unfastened, the pump in the tank does not start.
    Fuel Pump Relay to OFF non-stop.

    Pressure below 10 bar


    and still, it should be much bigger.


    So if you can't see fuel with the injection tube unscrewed (while shooting) then I should suspect the CR pump?
  • #7
    szymitsu21
    Moderator of Cars
    Definitely yes.
    The diagnosis is almost 100%



    I read it backwards and I forgot that after blinding the return the car starts.
    So my diagnosis is not 100% accurate ..
  • #8
    mario03369
    Level 14  
    Check the injectors on the overflow.
  • #9
    rogale2
    Level 9  
    mario03369 wrote:
    Check the injectors on the overflow.


    Why check the injectors if the fuel does not reach the rail?

    Could someone tell me what the opening level of the pressure regulator on the CR pump should be during start-up?
    For me, the level fluctuates around 40% during start-up. And when working with a blind return to the tank, there is also 40%.

    Should the controller be adapted after replacing it?
  • #10
    mario03369
    Level 14  
    rogale2 wrote:
    During firing, the pressure on the rail is 80-100 bar, while the expected ~ 300bar.


    If there is no fuel, what does the pressure of 100 bar do there?

    At such a pressure, the injection or the regulator is released.
  • #11
    EndrjuWiwi
    Level 10  
    rogale2 wrote:


    So if you can't see fuel with the injection tube unscrewed (while shooting) then I should suspect the CR pump?


    It is more than possible. Maybe there are micro-leaks at the pump. Even this 1300 is the pressure "oh, oh, oh god." The head could have released somewhere or the seals to be replaced. As you drove so much time on emergency you could have gotten the high pressure pump completely. Where are you from? There are good pump-makers in Stalowa Wola, in Bosch, find yourself on the net so that I do not do advertising. Good luck.
  • #12
    rogale2
    Level 9  
    Ok. I replaced the fuel pump in the tank and the car starts. Apparently the fuel pump was giving too little pressure to enter the CR pump.

    Currently, the car goes into emergency mode or goes out only during strong acceleration around 2500-3000 revolutions.

    Ducato 3.0 - low fuel pressure - Low fuel pressure on the rail.

    Error P0091 appears when the car enters emergency mode.
    Error P0092 appears when the car goes off.

    During acceleration, the expected pressure differs from the actual pressure by about 200-300 bar (around 2500 revolutions and gas to the floor).
    I did an injection overflow test. The injections are flowing evenly as normal.

    Now I wonder if the CR pump is just not efficient anymore. But the error shown on the computer clearly says that the regulator on the input to the pump has the wrong signal. It is a pity that the error is not described in more detail, but my reason is the low pressure system before entering the pump.

    Anyone advise something?
  • #13
    1986misza
    Level 2  
    Hello,

    Was it possible to establish something because I have identical symptoms and 6,000 invested and it still doesn't work like you
  • #14
    damian475
    Level 17  
    The best way is to sprinkle the cr pump and the injectors. Pre-injectors for overflow.
    Because there will be a problem here.
  • #15
    1986misza
    Level 2  
    Injectors bought new on the iveco service, the pump checked in the Bosch service and the problem is still the same
  • #16
    pancurp10
    Level 11  
    and the sensor on the rail was replaced?
  • #17
    pablock
    Level 2  
    Was the problem resolved? I have the same, the pump in the tank has been replaced, the toilet pump has been replaced, the valves have been replaced, the timing has been checked, the new pipes to the tank have been released, the car fires after the return from the pump is throttled and shows 1600bar on the rail and this is the same on the pressure gauge, it goes out after adding gas.
  • #18
    decumanus
    Level 2  
    As a comment, I will describe my story, it also went out when adding gas (P089, 091, 092), sometimes when changing gear, the regulator was replaced, the pump in the tank was making noise (I presumed that the safety valve is working) new filter ... After all, the car was barely going. The mechanic, after finally getting to the high pressure pump, pulled some hard sawdust from the intake stub. Probably once, someone did not change the filter for so long until it fell apart. The inlet was clogged, so the return flow to the tank was also weak, hence the pump "gave sideways"
    Maybe a hint will be useful to someone.
    Raphael
  • #19
    Maciej 900
    Level 1  
    Has anyone fixed the problem? everyone is looking for an answer, but when I solve the problem, it was necessary to write what was the reason.