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    Need some help diagnosing a fuel system issue

    Hey gents.

    So I parked my car two years ago after some minor clutch issues came up and haven't had time to circle back to it until today. Its sadly been untouched since then. I threw in a new battery, 8 gallons of fresh gas (was nearly empty), checked all fluids, and tried to get it running. Car cranks well but does not want to start. Managed to get it going for a few seconds with some starter fluid in the air filter housing but no luck beyond that.

    New fuel pump was installed about a year before I parked the car (so 3ish years) and has about 20-25k miles on it. I know these go bad when they sit for an extended period of time (internal check valve X moisture, or otherwise), but the pump primes very audibly. I removed the rear seat, checked connections, gave it a few small hits of a mallet, and even pulled the attached fuel hose/line under crank for a split second to confirm that fuel is getting to, and/or through, the pump. Fuses check out okay. Haven't checked the relay but seems thats not my issue. Also fiddled with the fuel sender for shits and giggles (which for some reason, when unplugged, still gives me a fuel reading on the cluster?).

    I have strong spark to the plugs, which I replaced today as well, but it seems they are not getting any fuel. Haven't checked fuel pressure from the engine bay because I don't see a schrader valve anywhere.

    So what gives? Do I have a compromised pump that can't get fuel to the engine? Or am I missing something here? Figured I would touch base with the boys before throwing another one in. Appreciate any insight. Thank you in advance.
    E46 M3 | C7 RS7





    #2
    Replace the fuel filter? While doing that you can check fuel pressure. There is a schrader valve near the fuel filter.

    If not that then pull the injectors and have them tested and cleaned.

    You still may have bad fuel in the lines even with fresh gas in the tank. If you change the fuel filter that should drain any bad fuel out of the lines.


    Sent from my iPhone using Tapatalk

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      #3
      As above.
      Varnished injectors perhaps.
      If the pump was very audible on prime, and not a brief hiss, it may be compromised.

      Comment


        #4
        Any faults, maybe you have an EWS issue?
        '09 HP2S, '12 R12GSA, '00 Black 323iT, '02 Alpine 325iT (Track Wagon), '02 Alpine 330iT
        Instagram @HillPerformanceBimmers
        Email to George@HillPerformance.com

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          #5
          Originally posted by George Hill View Post
          Any faults, maybe you have an EWS issue?
          If it was EWS it wouldnt start with the starter fluid.


          Sent from my iPhone using Tapatalk

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            #6
            Originally posted by eacmen View Post
            Replace the fuel filter? While doing that you can check fuel pressure. There is a schrader valve near the fuel filter.

            If not that then pull the injectors and have them tested and cleaned.

            You still may have bad fuel in the lines even with fresh gas in the tank. If you change the fuel filter that should drain any bad fuel out of the lines.


            Sent from my iPhone using Tapatalk
            I've got a new filter sitting in the trunk so will start with the small item and then work towards injectors/pump. Will try the schrader valve down there as well.

            Originally posted by FBloggs View Post
            As above.
            Varnished injectors perhaps.
            If the pump was very audible on prime, and not a brief hiss, it may be compromised.
            Very audible but with the seat removed. Although during cranking, when going back and forth to ignition 2 with the key, it seems to prime for an extended period of time, perhaps too long. Starting to lean towards compromised pump at this point.

            Originally posted by George Hill View Post
            Any faults, maybe you have an EWS issue?
            No codes or faults.

            ​​​​​​​Thank you gents. Will report back in the coming days.
            E46 M3 | C7 RS7




            Comment


              #7
              Originally posted by eacmen View Post

              If it was EWS it wouldnt start with the starter fluid.


              Sent from my iPhone using Tapatalk
              EWS might only cut off the fuel but not sparks. But to be sure, OP should check the EWS status using INPA software tool.

              Comment


                #8
                Originally posted by Boost View Post

                1. Very audible but with the seat removed. Although during cranking, when going back and forth to ignition 2 with the key, it seems to prime for an extended period of time, perhaps too long. Starting to lean towards compromised pump at this point.
                2. No codes or faults.
                1. I don't think it's a bad pump.
                2. Need to read the EWS module status.


                Comment


                  #9
                  Originally posted by sapote View Post
                  EWS might only cut off the fuel but not sparks. But to be sure, OP should check the EWS status using INPA software tool.
                  Wouldn’t EWS prevent starter solenoid from closing?


                  Sent from my iPhone using Tapatalk

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                    #10
                    Originally posted by eacmen View Post

                    Wouldn’t EWS prevent starter solenoid from closing?
                    EWS does (2) things to prevent starting.

                    1. EWS to Key if out of alignment the car will not crank.
                    2. EWS to DME if out of alignment the car will not light off.

                    So you can have an EWS issue and have (2) symptoms, no crank OR no start.
                    '09 HP2S, '12 R12GSA, '00 Black 323iT, '02 Alpine 325iT (Track Wagon), '02 Alpine 330iT
                    Instagram @HillPerformanceBimmers
                    Email to George@HillPerformance.com

                    Comment


                      #11
                      Originally posted by George Hill View Post

                      2. EWS to DME if out of alignment the car will not light off.
                      Not light off as in not start?

                      I'm finally getting back to this so starting to put together a list of things to address/check out.
                      E46 M3 | C7 RS7




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                        #12
                        I think not light off as no fire in the combustion -- no spark and no injected fuel.

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                          #13
                          Originally posted by Boost View Post

                          Not light off as in not start?

                          I'm finally getting back to this so starting to put together a list of things to address/check out.
                          the car will not start.

                          '09 HP2S, '12 R12GSA, '00 Black 323iT, '02 Alpine 325iT (Track Wagon), '02 Alpine 330iT
                          Instagram @HillPerformanceBimmers
                          Email to George@HillPerformance.com

                          Comment


                            #14
                            Well, I finally figured out why the fuel pump was priming but the car wasn't starting..



                            E46 M3 | C7 RS7




                            Comment


                              #15
                              Originally posted by Boost View Post
                              Well, I finally figured out why the fuel pump was priming but the car wasn't starting..
                              Did you fix the broken hose or replace the pump? Mileage on the pump?

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