Almost ready! No spark, no fuel. Help!

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • kylelauffer
    Banned
    • Dec 2009
    • 624

    #16
    Originally posted by weaksauce
    the fuel pump on my e30 only runs when the engine is cranking. i just was messing with my injectors. of coarse that is on a 1984 325es running the original electronics.
    yes that is correct!! you only get fuel when cranking on these cars.

    i thought that until i cracked open my fuel lines and let them hang. then started cranking and fuel came out. you can also check and see if your computer is working by checking if your injectors are pulsating. put a test light to the 12 volt battery. put the light to the injector signal and see if the test light is blinking while cranking.

    and for spark you should follow the wires back from the coil. when key is turned but no cranking there should be power to both sides of the coil.

    and make sure you have the red wire that runs off those relays are hooked up to power not ground

    Comment

    • Jean
      Moderator
      • Aug 2006
      • 18228

      #17
      Originally posted by Jb325is
      So should I have ground at the brown wire on the back of the relay or not?
      No additional wires other than the 2 grounds near ignition wires, and 1 red wire for battery positive. Rest is battery to starter, starter to alternator sub-harness.
      Mtech1 v8 build thread - https://www.r3vlimited.com/board/sho...d.php?t=413205



      OEM v8 manual chip or dme - https://www.r3vlimited.com/board/sho....php?p=4938827

      Comment

      • Jb325is
        R3VLimited
        • Oct 2003
        • 2137

        #18
        Used this post to do some troubleshooting today:

        Thanks jlevie!

        Everything checked out fine, except for pin 27 on the DME. I don't get power there at any time, OFF ON or START. Is this the voltage supply for the DME or is it an output? Since its the only thing between the ignition switch and the coil, I'm guessing its the supply, but would that cause the coil to not get power?
        - '88 m54 coupe

        <3

        Comment

        • Jean
          Moderator
          • Aug 2006
          • 18228

          #19
          See if the ETM has the DME pin outs on there, that way you can trace it :)
          Mtech1 v8 build thread - https://www.r3vlimited.com/board/sho...d.php?t=413205



          OEM v8 manual chip or dme - https://www.r3vlimited.com/board/sho....php?p=4938827

          Comment

          • Jb325is
            R3VLimited
            • Oct 2003
            • 2137

            #20
            Originally posted by Jean
            See if the ETM has the DME pin outs on there, that way you can trace it :)
            I did, it says it connects to the wire that supplys the + side of the coil.. That's terminal 15 from the ignition switch. I suppose this means I have an issue with either my ignition switch or DME, both of which worked fine before the swap. How common is it for ignition switches to fail like that? I still get power to my accessories, guages, starter, etc.. Doesn't make much sense
            - '88 m54 coupe

            <3

            Comment

            • Jean
              Moderator
              • Aug 2006
              • 18228

              #21
              That is odd... I can ship you my stock dme to try, just ship it back when you are done?
              Mtech1 v8 build thread - https://www.r3vlimited.com/board/sho...d.php?t=413205



              OEM v8 manual chip or dme - https://www.r3vlimited.com/board/sho....php?p=4938827

              Comment

              • Jb325is
                R3VLimited
                • Oct 2003
                • 2137

                #22
                Yeah that'd be great if you could do that, I'm a bit skeptical that mine died just from sitting around for a couple months but couldn't hurt to eliminate it as a possibility.
                - '88 m54 coupe

                <3

                Comment

                • Jean
                  Moderator
                  • Aug 2006
                  • 18228

                  #23
                  PM me your address again, I'll mail it out on monday to you.
                  Mtech1 v8 build thread - https://www.r3vlimited.com/board/sho...d.php?t=413205



                  OEM v8 manual chip or dme - https://www.r3vlimited.com/board/sho....php?p=4938827

                  Comment

                  • Jb325is
                    R3VLimited
                    • Oct 2003
                    • 2137

                    #24
                    Might not need it, just tested the e30 c101 and I'm getting battery voltage at pin 6 (terminal 30, main relay and fuel pump relay) with the key on but not pin 7, which is coil positive and DME input (pin 27) if Im not mistaken. In my mind, this points to either a ground issue or ignition switch, am I on the right track?

                    edit: Just tested the ignition switch connector and I have power to the green wire at the connecter next to the steering column, can't figure out if it's going to the ignition switch or coming from it.

                    2nd edit: It's coming from the ignition switch, I have power to the green wire at the ignition switch, out of the ignition switch connector, but then lose it between the ignition switch connector and the C101 connector.
                    Last edited by Jb325is; 02-21-2010, 06:04 PM.
                    - '88 m54 coupe

                    <3

                    Comment

                    • Jb325is
                      R3VLimited
                      • Oct 2003
                      • 2137

                      #25
                      I think I tracked it down.. After looking through the wiring diagrams more last night I found that power to pin 7 on C101 and pin 27 on the DME go through the OBC relay. I haven't been able to check it yet but I'm betting a jumper from terminal 30 to 87 on that relay might solve my issue. One thing I dont quite understand is I heard talk of a security code used at the obc, is this what turns on the relay?
                      - '88 m54 coupe

                      <3

                      Comment

                      • Jb325is
                        R3VLimited
                        • Oct 2003
                        • 2137

                        #26
                        Jumped the red/green and green wires on the obc relay and it cranked right up! Now I just have to figure out how to make it work without the jumper wire
                        - '88 m54 coupe

                        <3

                        Comment

                        Working...