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    #31
    any updates?

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      #32
      I do have an update!

      Since my last update, I swapped in my freshly rebuilt 19# injectors (thanks MEPEH). I've also installed a custom SSSquid chip to match my mods (thanks SSSquid).

      After swapping in the new chip, the idle was almost perfect for two days. Then on day 3 it would not idle at all. I swapped ECU's to a stock one, it idled but it was really rough. I immediately swapped back to the SSSquid chipped ECU thinking the ECU had failed and wanted to verify. It idled to my surprise and it was rough but not as rough as the stock ECU. The next day the idle improved again to what I would consider a steady, but slightly rough idle (still on chipped ECU). What I've concluded but cannot verify yet, is that I have a short in the wiring harness inside, or very near the ECU connector.

      This would explain everything including why all sensors test ok at the sensor and at the ECU. I'm assuming that when I'm pulling the harness out to test that the short is not present, but sometimes when it's plugged in the short occurs. I'm also assuming that since the rough idle (when occurring) improves when the car warms up, that it could be a short in the temp sensor signal wire. I have not yet been able to verify this.
      90 325i DD/Track
      03 Durango 5.9


      Originally posted by e30mpg
      It is recommended to get new gasket but this is R3v and we just copper spray that shit......slap biotch on and tighten to tq.

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        #33
        Check all of your grounds! It can be very tedious and take forever but check and double-check them, because often that ends up being the case with hard-to-diagnose bad idles.

        Cheers and good luck!

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          #34
          update?
          BMW tech
          Umass Amherst
          05 wrx sti

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            #35
            Final update for now.

            I previously checked grounds, many months ago.

            I'm about 95% sure it's a short in the wiring harness near or inside the ECU connector. Every time it acts up, I mess with the harness connector to the ECU and it gets much better. It usually involved disconnecting and reconnecting it. I'm also thinking the short is one of the wires associated with the CTS, TPS, or AFM, but I can't be sure because when I have it unplugged while testing, it always tests fine.

            I have NO motivation to replace the wiring harness right now, so I'll just live with it until the suspect wire completely separates. Then I'll be able to pinpoint the exact wire and fix it without messing with the entire harness.

            I hope all my exploits with this issue help others in their trouble shooting.
            90 325i DD/Track
            03 Durango 5.9


            Originally posted by e30mpg
            It is recommended to get new gasket but this is R3v and we just copper spray that shit......slap biotch on and tighten to tq.

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              #36
              I would also like to add that I have also changed my setup since the initial posts.

              I know have:
              Setup
              M20B25 - stock short block
              Rebuilt Head with Schrick 272 cam
              Headers
              19# injectors
              SSSquid chip - I get better mileage with this chip than I did with Mark D.
              90 325i DD/Track
              03 Durango 5.9


              Originally posted by e30mpg
              It is recommended to get new gasket but this is R3v and we just copper spray that shit......slap biotch on and tighten to tq.

              Comment


                #37
                Hey 603Racing how smooth is your idle with the Schrick 272 cam vs the stock camshaft? My car has a little bit of a roughness but I can't tell if its a characteristic of the 272 or an idle issue. It seams to gallop a little, in a very steady pattern.

                I also did an e2i swap, the 272 is the only cam I've had in this engine so I have nothing to compare it with. I'm running a stock 173 ECU and exhaust also.
                - 1982 528e e28 m20b27, e2i, schrick 272

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                  #38
                  How hot does your ECU get?

                  90% of owning a German car from the 80-90's is tracking down electrical problems.... Hurray.

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                    #39
                    Originally posted by squidmaster View Post
                    How hot does your ECU get?

                    90% of owning a German car from the 80-90's is tracking down electrical problems.... Hurray.

                    Good question! I'll take a look next time I drive it.

                    Ahh yes the joys of electrical troubleshooting. lol I hate torpedo fuse boxes. e30's have a blade fuse box option don't they? from the late 80's early 90's right? That could solve some issues right there. lol
                    Last edited by delorean175; 08-04-2016, 08:11 PM.
                    - 1982 528e e28 m20b27, e2i, schrick 272

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                      #40
                      They sure do. No one likes torpedo fuses.... The 190e has torpedo fuses for all years (up to 93! wtf!) and it's a mess. At least you know when torpedo fuses are blown, because they've either exploded and are MIA, or something smells like it's about to catch fire.

                      The 272 cam will give you a rough idle if you're not tuned for it, but it shouldn't be *too* horrible with stock software

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                        #41
                        Originally posted by squidmaster View Post
                        How hot does your ECU get?

                        90% of owning a German car from the 80-90's is tracking down electrical problems.... Hurray.
                        I finally got around to checking the temp of my ECU after a drive. It gets warm but not hot. Is it supposed to be cold or something?


                        Originally posted by squidmaster View Post
                        They sure do. No one likes torpedo fuses.... The 190e has torpedo fuses for all years (up to 93! wtf!) and it's a mess. At least you know when torpedo fuses are blown, because they've either exploded and are MIA, or something smells like it's about to catch fire.

                        The 272 cam will give you a rough idle if you're not tuned for it, but it shouldn't be *too* horrible with stock software
                        Good to know, I'm happy to hear nothing is wrong then. My idle doesn't bother me. I guess it's time to move on to the next issue then. lol

                        Thats ridiculous the 190e used torpedo fuses so far into to the 90's. lol I have hope for my e28, the e24 had a blade fuse box in 1989 (last year it was produced) I got one and I'm trying to figure out how to make it fit while looking like it belongs there. I have all my important fuses ziptied in place. lol
                        - 1982 528e e28 m20b27, e2i, schrick 272

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                          #42
                          Wait, a cam will give you a rough idle if your not tuned for it? Since when can the ecu effect your cam on these motors? What are you talking about?


                          Sent from my iPhone using Tapatalk
                          The best one-stop shopping for German car parts and lifestyle: http://www.gutenparts.com/

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                            #43
                            Originally posted by delorean175 View Post
                            I finally got around to checking the temp of my ECU after a drive. It gets warm but not hot. Is it supposed to be cold or something?
                            Warm is fine, but hot means you have a grounding issue with the ECU, or a circuitry issue within.
                            Originally posted by berlow94 View Post
                            Wait, a cam will give you a rough idle if your not tuned for it? Since when can the ecu effect your cam on these motors? What are you talking about?


                            Sent from my iPhone using Tapatalk
                            Longer duration cams require more ignition timing and sometimes a higher idle (depending on how long it is) to mitigate the roughness in idle that is caused by the difference in duration and/or lift. This is the case with all cars, not specific to E30s. The ECU has absolutely no way of adjusting for differences in an upgraded cam, especially on cars without variable valve or cam timing.

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                              #44
                              Any updates?

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