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    #16
    PIP is the base spark signal. It does not change when the SPOUT is connected or disconnected. SPOUT influences computed timing. Which is influenced by MAP (Load), RPM and ECT. If you have a bad ECT sensor signal, it's gonna do stupid things.

    Comment


      #17
      Is your +5v vref signal where it should be? All of those sensors you get codes for run off that line. If the ECM is internally retarded and the 5v source is not working, nothing else will work right either. These things are 30 some years old, probably needs a re-cap at this point.

      There should also be a ground somewhere on the engine from the ECM harness. I don't know where it is on the CFI cars, but back of the intake or back of the head is probably a good guess. Thats the negative return for all of the engine-mounted sensors. There is also an ECM ground going straight to the battery in a small black wire. Make sure both of those are connected and good.

      If you've got the breakout box wired up, see how the voltage is on the ECM power input connection, the one that comes from the relay. If it isn't stable, the ECM will not work right either. Problems there usually point to flaky relays. Wouldn't be a terrible idea checking output voltage to the fuel pump for the same reason. Do this while its not running well, otherwise it won't capture anything of use.
      86 Lincoln Town Car (Galactica).
      5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley

      91 Lincoln Mark VII LSC grandpa spec white and cranberry

      1984 Lincoln Continental TurboDiesel - rolls coal

      Originally posted by phayzer5
      I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousers

      Comment


        #18
        VREF was 4.63V at the ECT. However it was 5.00V at the TPS. Those were the two I checked it at since they were the two that seemed most directly related to my problems. Otherwise I was checking the readings at the BOB.

        There is a ground (two in one, for the TFI wiring shield and out of the wiring) directly beside the hood strut, and another one into the back of the passenger side cylinder head, which is a real bear to get to. I had completely removed the harness from the car, and when reinstalling it, I cleaned up both of those ground points. There is no other harness-to-body ground that I'm aware of, the other one (two wires) goes directly to battery negative.

        Problem with the BOB is I can't keep it hooked up and drive the car. There's no room to tuck it under the hood and close the hood enough to latch. And I tried but was not able to hook up the BOB inside the car, no room under the dash for the giant clunky connector. So under the hood it must go, and that means no driving.

        The ECM was getting (via the relay) full battery voltage, however, it is true that I haven't seen what it was getting in the exact moments of trouble.

        So, here's what happened today:

        Went to the junkyard. '85 Grand Marquis ECM and chunks of harness were already missing. '85 Crown Vic ECM still present, and harness complete except the injector connector which was snipped off and the self-test connector has a torn wire. Complete enough for my purposes, and repairable if I need it for whatever reason. Also bought the front bumper off an '81 Mark VI and the rear door switch panels which I've needed for a while, so it was a productive trip. Going back for some more stuff I forgot to take.

        Got home, opened the ECM, looked for bulging caps or burnt traces...no visible problems. Installed it. Original is of course an E4, with catch code SG. The 'new' one is an E5, with catch code MN.

        Fired right up, no problem. Cold idled great. Went for a good drive, car felt awesome. All the way up the temp gauge to 190, flawless. I shut it off and let it heat soak up to 220, then started it up, and everything was still flawless. Seemed good right?

        Well, started driving back home from the spot I'd stopped to let it heat soak. Still great. Hit the expressway, still great. Tons of mid throttle response, drives like a new car. Was so happy. But when I came up to my exit and a stop light, it started missing (the same sensation as before, except less severe - perhaps not enough to spill a coffee if you left it on the dash, where before, the cup would have been launched off the dash with how violently it was jerking).

        Accelerating away from the light, smooth. Was fairly gentle with it (previously it would have been bucking and jerking like crazy with only a little bit of throttle like that). But, each time I stopped, the miss came back.

        Continued driving to see what would happen. Eventually it picked up a little bit of a jerk just ever so slightly at throttle tip-in, like when you're just going to creep up to a stop sign after the car in front goes.

        I specifically tested for the miss when trying to maintain speed without decel/accel, and it no longer has that problem. It will maintain speed smoothly now.

        KOEO/CM 11 11
        KOER 33
        At the time of doing the tests, I checked the fuel pump and ECM relays, and the ECM relay was quite hot to the touch (but fuel pump was not). Swapped it with a junkyard pull I had in the trunk as a roadside spare. No change in behaviour, but figured it was worth a shot. Had no means at the time to see voltage drop across it.

        At least I no longer have a wall of codes, but I have a feeling the EGR not opening is not the cause of my problems...

        Drivability is way, way up. The car is usable again. It just has these lingering issues.
        Last edited by kishy; 12-03-2016, 08:12 PM.

        Current driver: Ranger
        Panthers: 83 GM 2dr | 84 TC | 85 CS
        | 88 TC | 91 GM
        Not Panthers: 85 Ranger | Ranger trailer | 91 Acclaim | 05 Focus
        Gone: 97 CV | 83 TC | 04 Focus | 86 GM
        | Junkyards

        Comment


          #19
          EGR not opening wouldn't actually cause this. By and large, when that doesn't work you'd never notice. If it sticks open or opens at the wrong time though, that you'd feel. Make sure the EGR valve itself actually works and holds vacuum. Most of the time thats the problem when you get a 33. I'd also pull it out of where it goes and make sure it isn't all packed up with carbon.

          The other possible is the EVR is bad, but thats easy enough to diagnose with a vacuum gauge. Hook one up and go for a drive. You should see it applying vacuum at various points. if it has vacuum in but no vacuum out, its not working. If its no vacuum or 8" immediately off idle, its sticky. It should apply variable vacuum, slowly increasing off idle. If it goes full open as soon as you give any pedal, it will stumble. Unhooking the vacuum line to the EGR is a quick way to rule that out. Shooting some wd40 or similar into the EVR may get it working properly if its sticky. Worked for me at least.
          86 Lincoln Town Car (Galactica).
          5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley

          91 Lincoln Mark VII LSC grandpa spec white and cranberry

          1984 Lincoln Continental TurboDiesel - rolls coal

          Originally posted by phayzer5
          I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousers

          Comment


            #20
            Originally posted by gadget73 View Post
            EGR not opening wouldn't actually cause this. By and large, when that doesn't work you'd never notice. If it sticks open or opens at the wrong time though, that you'd feel. Make sure the EGR valve itself actually works and holds vacuum. Most of the time thats the problem when you get a 33. I'd also pull it out of where it goes and make sure it isn't all packed up with carbon.

            The other possible is the EVR is bad, but thats easy enough to diagnose with a vacuum gauge. Hook one up and go for a drive. You should see it applying vacuum at various points. if it has vacuum in but no vacuum out, its not working. If its no vacuum or 8" immediately off idle, its sticky. It should apply variable vacuum, slowly increasing off idle. If it goes full open as soon as you give any pedal, it will stumble. Unhooking the vacuum line to the EGR is a quick way to rule that out. Shooting some wd40 or similar into the EVR may get it working properly if its sticky. Worked for me at least.
            That...is worth investigating. When I bought the car the vac line was unhooked off the EGR valve. I figured it was because the valve was sticky (and it was). Replaced valve with a good one (very good, very smooth, not carboned up) and hooked it back up. The installed valve does not have any problem, but the sensor could be faulty (meaningless other than setting codes) and the EVR is unknown.

            It's weird on CFI, the EGR seems to be fed with vacuum from two solenoids. I haven't quite worked out how it works.

            However the car (old ECM) still had the same problems even with the emissions vacuum system completely capped off. Worth a retry now though.

            As an aside (maybe related, who knows). The '85 system uses a spacer under the throttle body, with a fatter looking EGR valve, where 84 I'm pretty sure it's just part of the intake, and the valve is not as fat (looks quite similar to the one on my 91, more or less). But functionally it should do the same thing.
            Last edited by kishy; 12-03-2016, 09:20 PM.

            Current driver: Ranger
            Panthers: 83 GM 2dr | 84 TC | 85 CS
            | 88 TC | 91 GM
            Not Panthers: 85 Ranger | Ranger trailer | 91 Acclaim | 05 Focus
            Gone: 97 CV | 83 TC | 04 Focus | 86 GM
            | Junkyards

            Comment


              #21
              Well...figured out why the EGR wasn't opening. I forgot to reconnect the vacuum line to the throttle body, which provides the vacuum for the solenoid/EVR. Whoops. That hasn't been like that long, just since the last time I poked around with the ACT (which is right under it).

              Information: the 1985 ECM is plug-and-play compatible with the 1984 harness, and therefore vice-versa. However, the 1985 engine harness cannot be mixed with the 1984 body electrical harness and ignition harness...without alterations. Minor ones, all the wires are the same, they're just in different connectors.

              Also, 1985 was the first year for the "new" TPS, which is the same TPS but with the new connector.

              I've now swapped the 1985 harness (complete engine+ignition) into my car, hoping to solve my issue, and had to make these alterations:
              • Solder in new injector pigtail, as it was missing from this harness
              • Chop and solder in the older style TPS connector. I had one on hand already I'd cut out of an EEC-III car (same connector)
              • The wire for the neutral safety switch goes through a different connector between these two years. I didn't want to chop up the connector in my car, so I added just the single pin terminal onto the end of the wire in the '85 harness, and heatshrinked it, so that's connected now.
              • There is something damaged about the trigger wires for the ECM relay in this harness. I used a jumper wire (a la EEC self test...) to power on the ECM so I could start it.
              • Eliminated low oil level sender (temporarily), as the donor car was a Vic, not a Town Car
              • IF I had opted to keep my 1984 ignition/charge wire harness half, I would have had to screw around with the two wires (one is tach signal, the other I don't remember what it does) where it joins into the ECM harness. In 1984 they are two single wire connectors. In 1985 they are together in one 2-wire connector.


              Obviously the issues are not great, but the net result is it functions. And the even more important result is that MY CAR NO LONGER MISSES! Or it just hasn't come back yet, whichever.

              Seems it may be time to go back over my original harness again, I must have missed something. Somewhere there is a damaged wire and it's screwing everything up. However I should mention that I did wiggle everything pretty thoroughly and did not find an issue by doing that.
              Last edited by kishy; 12-04-2016, 05:03 AM.

              Current driver: Ranger
              Panthers: 83 GM 2dr | 84 TC | 85 CS
              | 88 TC | 91 GM
              Not Panthers: 85 Ranger | Ranger trailer | 91 Acclaim | 05 Focus
              Gone: 97 CV | 83 TC | 04 Focus | 86 GM
              | Junkyards

              Comment


                #22
                Did you try the other ECM with your original harness?
                86 Lincoln Town Car (Galactica).
                5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley

                91 Lincoln Mark VII LSC grandpa spec white and cranberry

                1984 Lincoln Continental TurboDiesel - rolls coal

                Originally posted by phayzer5
                I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousers

                Comment


                  #23
                  Originally posted by gadget73 View Post
                  Did you try the other ECM with your original harness?
                  I did, that was the setup where it was missing again but the missing was subdued and not happening as much.

                  So that does mean despite my multimeter efforts there is a flaky spot in my original harness that I missed.

                  The next test I suppose is my original ecm with the new harness. Also I need to fix the 85 harness ecm power relay problem to continue using it, currently I have to open the hood and install the jumper wire to power on the ECM. But as a temporary measure I can at least do my errands today.

                  Current driver: Ranger
                  Panthers: 83 GM 2dr | 84 TC | 85 CS
                  | 88 TC | 91 GM
                  Not Panthers: 85 Ranger | Ranger trailer | 91 Acclaim | 05 Focus
                  Gone: 97 CV | 83 TC | 04 Focus | 86 GM
                  | Junkyards

                  Comment


                    #24
                    Figured out why I had to jump the relay. In 1985 the ignition switch wire to turn on the relay moved out of the connector it was in for 1984, into the 2-wire connector shared with the neutral safety switch which is a new connector for 1985.

                    With a bit of an ugly, but electrically sound splice, I no longer have to pop the hood and jump the relay

                    Also found where the oil level wire goes and added it. So it's now complete.

                    I will be working to figure out what's wrong in my original setup, and if it's a wiring defect in the harness, fix it so I have a functional spare. I'll also post here with what I found the problem to be. For now though, I just want to enjoy my smooth running car again.

                    '81 Mark VI bumper installed, too, so she's looking alright too now.

                    Thanks, everyone, for your input and patience.

                    Current driver: Ranger
                    Panthers: 83 GM 2dr | 84 TC | 85 CS
                    | 88 TC | 91 GM
                    Not Panthers: 85 Ranger | Ranger trailer | 91 Acclaim | 05 Focus
                    Gone: 97 CV | 83 TC | 04 Focus | 86 GM
                    | Junkyards

                    Comment


                      #25
                      Cool man, glad you had the patience and determination to get through it and not put a carpitator on it.
                      1985 LTD Crown Victoria - SOLD
                      1988 Town Car Signature - Current Party Barge

                      Comment


                        #26
                        Good deal. Electrical stuff can be annoying, and I suspect its probably the biggest source of "fuck this shit" sentiment on cars.
                        86 Lincoln Town Car (Galactica).
                        5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley

                        91 Lincoln Mark VII LSC grandpa spec white and cranberry

                        1984 Lincoln Continental TurboDiesel - rolls coal

                        Originally posted by phayzer5
                        I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousers

                        Comment


                          #27
                          Originally posted by gadget73 View Post
                          Good deal. Electrical stuff can be annoying, and I suspect its probably the biggest source of "fuck this shit" sentiment on cars.
                          This. I'm pretty good at fixing electrical crap on cars, but there's a certain point where I say screw it. Thankfully I have yet to reach that point with any of my own cars... I know someone who has reached that point with one of my cars and I'm really sorry he had to deal with it when leaving the system stock and tuning that would probably have been so much better.

                          Only two things are infinite, the universe and human stupidity, and I'm not sure about the former. -- Albert Einstein
                          rides: 93 Crown Vic LX (The Red Velvet Cake), 2000 Crown Vic base model (Sandy), 2003 Expedition (the vacation beast)
                          Originally posted by gadget73
                          ... and it should all work like magic and unicorns and stuff.
                          Originally posted by dmccaig
                          Overhead, some poor bastards are flying in airplanes.

                          Comment


                            #28
                            heh. There are reasons my harness remains largely stock. Its modified somewhat, but at it's core it remains pretty true to the original 1986 construction. I could revert it back to stock with very minimal effort if I needed or wanted to.
                            86 Lincoln Town Car (Galactica).
                            5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley

                            91 Lincoln Mark VII LSC grandpa spec white and cranberry

                            1984 Lincoln Continental TurboDiesel - rolls coal

                            Originally posted by phayzer5
                            I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousers

                            Comment


                              #29
                              Originally posted by gadget73 View Post
                              ..."fuck this shit"...
                              Originally posted by sly View Post
                              ...screw it...
                              Oh, don't I know those sentiments...

                              Basically my drive here was connected to a few key ideas:
                              1. Everyone says to get rid of CFI because it will never run right. I'm stubborn. 2+2...
                              2. I kinda like electrical work. I'm medium-high skill level for wire-wire and through-hole soldering (maybe better than that, I just generally assume I'm not going to be the best at something self-taught), and I like figuring out electronic issues...even if they can be a bear sometimes. I'll take electrical over turning bolts any day.
                              3. The car had ran great intermittently in my ownership of it, so obviously the answer was something non-catastrophic. There was a period where I started to question compression but it's not an issue.


                              It's smooth as glass now. I'm kinda looking forward to finding the problem in my original harness. Whatever the problem is, that harness will be repaired, even if it means all new pigtails on it and a bunch of wires replaced.
                              Last edited by kishy; 12-07-2016, 10:25 AM.

                              Current driver: Ranger
                              Panthers: 83 GM 2dr | 84 TC | 85 CS
                              | 88 TC | 91 GM
                              Not Panthers: 85 Ranger | Ranger trailer | 91 Acclaim | 05 Focus
                              Gone: 97 CV | 83 TC | 04 Focus | 86 GM
                              | Junkyards

                              Comment


                                #30
                                "Fuck this shit" is pretty much how I feel about most things electrical, lol. Just looking at a bundle of wires makes me blow a breaker in my head. Nuts and bolts, heavy lifting is no problem, but i'll farm out electrical any damn day. You guys are saints.

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