Engine & Gearbox warm engine starting issue, whistling pressure pump

Discussion in '8th Generation (2008-2015) [Acura TSX]' started by turkpet, Thursday 10th Sep, 2015.

  1. turkpet Junior Member ☆ ☆ ☆ ☆ ☆

    I have got a problem with my 2,2 I-DTEC ...When the engine is cold, no problem at all, no problem during driving even when it is warm.., but as soon as I stop warm engine and wait for about 5-10 minutes, it will not star! Starter doing its job well,but engine won't start... You can hear just fading whistling sound out of pressure pump ..when turning ignition key to position II - again fading whistling sound...and so on(or someting like bzzz...) After 1,5-2 hours starting without any problem without any whistle sound..
    Honda servis 10 days after looking for problem with no success,no warnings on diagnostics, every day they change their theory and I am upset... (diesel injectors send to Bosch service- its o.k, engine revs semsor changed -no success..)
    I would really appreciate any help
    My video:

  2. Zebster Guest

    If it was the older I-CTDI engine then I'd suggest that the fuel rail over-pressure relief valve was leaking, as this common problem can often result in starting problems that are worse with a warm engine...
    How to diagnose and replace a faulty over pressure relief valve on a 2006 2.2 i-CTDi - Civinfo

    I have no experience with the I-DTEC, but it appears to have a similar valve on the fuel rail, which discharges into the return pipe, item #3 on this schematic...
    So it might be worth pulling off the pipe, plugging it, then fitting a length of pipe from the rail valve to a container, then running the engine to check that no fuel is discharged, in a similar way as in that link for the older engine.
    Last edited by a moderator: Thursday 10th Sep, 2015
  3. turkpet Junior Member ☆ ☆ ☆ ☆ ☆

    Thank's.. I thought about it , but you know..I didn't want to interfere with their know-how( as I see a very poor one), but I will..
    I think There are two over pressure valves:the first one,as you notice, on pressure rail, another on pressure pump, and maybe this one has gone in my engine
    It's not the kind of my issue bellow, just position of valve on fuel pressure pumpe:
    Bulletins & Advisories - CR-V I-DTEC Diesel High Pressure Fuel Pump Noise
  4. Zebster Guest

    That other HK thread about fuel pump noise doesn't mention that issue causing a starting problem.

    Yes, the older diesel engine also has a 'leak back' line from the fuel pump that shares a return to the fuel tank with the fuel rail over pressure valve (and the fuel injector combined leak backs). But I've never heard of this being a problem and I don't know if any fuel should normally flow from this pump leak back pipe. However, there should be NO fuel coming from the rail valve (in normal operation), so its very easy to assess if that valve has developed a fault by easily checking yourself using a similar method to the Civinfo link I posted yesterday.

    If it is that rail valve then - if possible - buy the replacement from Bosch, not Honda! For the I-CTDI, Honda will usually make you buy an entire new rail, which is more than ten times the cost of the valve from Bosch.
  5. turkpet Junior Member ☆ ☆ ☆ ☆ ☆

    ..I Will try...yon know: Clear bzzzzz....from pressure pump with vibrating return pipe.... That's why I thought about pump valve problem and no rail valve problem
  6. Zebster Guest

    I can't be sure, as I've never even seen an I-DTEC engine in the flesh. Does yours still make that noise with a full fuel tank?
  7. turkpet Junior Member ☆ ☆ ☆ ☆ ☆

    Yes, and never empty tank
  8. turkpet Junior Member ☆ ☆ ☆ ☆ ☆

    H servis: they know about I-CTDI and rail regulator valve issue, they have aftermarket Bosch valves for this engine, but there is not aftermarket for I-DTEC. No single pump overflow valve just the whole pump. So I asked them to check the both parts ( rail valve and pressure pump) and I'll see
  9. Zebster Guest

    It isn't a rail regulator, it's an engine protection device in the event that the rail pressure becomes excessive (rail pressure has to be variable depending on load conditions, etc, and is actually contiuously controlled by the ECU via a bypass solenoid in the fuel pump, using pressure signals from a piezo pressure sensor on the rail). Because its a protection device, the valve should never operate in normal conditions, therefore its really easy to test... If fuel is being emitted, then its faulty!

    Good luck. Please do report back when you have an answer.
  10. turkpet Junior Member ☆ ☆ ☆ ☆ ☆

    I know that, but not sure about H technician .., More item replacement than thinking about problem- I have gotimpression.Thanks for now, I will refer
  11. Zebster Guest

    If Honda fail to find the problem, then you could always consider taking it to a diesel specialist who is familiar with the Bosch common rail system. It's a fairly common system that is widely understood.
  12. turkpet Junior Member ☆ ☆ ☆ ☆ ☆

    Latest news: I took my car from Honda servis and good by for ever. Contacting Bosch servis and next week for cheque . Afternoon Making test:turning key to position II and pressing overpressure return pipe from pressure pump and loud whistling as a proof of leak.. Pressing returne pipe from rail valve with no sound !
    Here's video:
  13. Zebster Guest

    Unfortunately the sound isn't working for me, so I can't tell if the engine is running? I guess that's proof that something is flowing down the pipe when I don't believe it should be (unless it's allowing air to be purged?). Hopefully the Bosch guys will have a better understanding and fix it for a reasonable pricei
  14. turkpet Junior Member ☆ ☆ ☆ ☆ ☆

    The engine is not running, just ignition key to position II( so tank fuel pump sending fuel to pressure pump)
    It's all clear now, because when return Pipe slipped down a little ( while pressing it to stop fuel in it leaking), a lot of fuel appeared leaking at the bottom.. I sliped pipe back and made a short video of leaking fuel..
    Conclusion: there is a huge leak of fuel to return pipe from pressure pump ( when preparing to start engine turning key to II position) so I guess there is pure pressure ( maybe no) in the rail.
  15. Zebster Guest

    This is beyond my experience. The I-CTDI does not have an electric fuel pump, so I cannot draw conclusions from these video clips.

    And I do not understand why the I-DTEC fuel pump needs an over-pressure return to the fuel tank... are you sure it's an over-pressure relief and not simply an air bleed?
  16. turkpet Junior Member ☆ ☆ ☆ ☆ ☆

    On Polish Bosch servis web this pipe is described as overflow of fuel..
    - - - Updated - - -
    Bosch CP4

    Attached Files:

  17. jimjams Guest

    I can't help with the OP's problem, but I was intrigued by the Polish in the image in the previous post.

    From what I can make out of the diagram, and a bit of translation of the Polish, and a bit of reading on the internet --- the pump is a 2-stage pump, having an internal "transfer pump" that supplies fuel from the fuel tank to the chambers of the high pressure pump. The fuel return is from a solenoid operated metering valve which regulates the fuel volume going between the transfer pump and the chambers of the high pressure pump.

    So my translation of the Polish is
    1 deactivator of the 3rd piston of the high pressure fuel pump (reduces the power absorbed by the high pressure pump if the vehicle is used at low load)
    2 high pressure fuel oulet
    3 fuel metering control valve (solenoid)
    4 fuel return from transfer pump
    5 fuel supply inlet
    6 mechanical adjustment of the transfer valve


    a nice picture from the first reference

    and a slide from a slide-show (which I can't find in my Chrome history, but the 2nd reference is a pdf with the same slides)

    I can only guess the the 7th Generation Accord diesel (I-CDTI or whatever) does not have the 2-stage pump, nor does it have a common-rail pressure as high as the 8th Generation Accord diesel (I-DTEC) ??
  18. Zebster Guest

    The I-CTDI uses a Bosch CP3 fuel pump, which is also a 2-stage pump (lift pump to suck the fuel up from the tank, plus a high pressure pump to achieve the required 1600 bar (max) fuel rail pressure. I would expect the I-DTEC to have a higher rail pressure.

    If the I-DTEC does have a 2-stage pump, then I'm surprised that it also needs an electric fuel pump.
  19. jimjams Guest

    I'm surprised that the Bosch CP3 was around 15 years ago (I'm including lead-time for design of the diesel engine in the 7th Generation Accord).
    But you lost me in #15 with "And I do not understand why the I-DTEC fuel pump needs an over-pressure return to the fuel tank... are you sure it's an over-pressure relief and not simply an air bleed?"
  20. turkpet Junior Member ☆ ☆ ☆ ☆ ☆

    Be sure It is a valve and pipe for excess fuel to get back to fuel tank... Of course air can pass through if air contaminated fuel system is