86 4wd d16a1 swap HELP!!!

I started this on another thread http://www.hondacivicwagon.com/bb/viewtopic.php?f=7&t=11856
when I was still not sure if I would even buy the car.

but it's in my hands now, so I thought I'd let y'all follow my progress and maybe if someone else does this in the future they'll have more info to go on.

so I bought it, it already has a d16a1 from an 86 integra installed. apparently it just bolted right in. prev. owner did the easy part!

doesn't have exaust or fuel, has engine wire harness but he didn't have the rest... :(

1st task was to obtain a 86-87 integra dash harness and ecu. possibly could have used 88-89 by swapping over dizzy as well. may yet, contemplating a turbo option in the future....

came across half a dozen 86-7 integras in the local yards, but they were all autos. finally found a manual and scored - it had an aftermarket cruise system on it too!

check it out:

Comments

  • it works by having a second throttle cable attached down low on the gas pedal. this is operated by a vacuum diaphragm, controlled by electronic module with a speed sensor inline to the speedometer cable. you can see it on the end of the cable. also, there is a vacuum switch that bolts to the clutch pedal to cut off the throttle when the clutch is depressed. operated by a third stalk added to the steering column.
  • JDMWago666JDMWago666 Senior Wagonist
    Can't wait to see the progress.
  • Me too, I'm planning to do the same thing to the same car minus the 4wd.
  • so I'm wondering about the VSS. on the back of both the integra and the wagon instruments is a snap-on attachment with a colored socket, inside is a circuit board. three wires go and plug into a socket just up and to the right of the speedometer cable plug. the plug going into the speedometer housing is the same on both clusters, but the wires are different colors. likewise, the plug going into the attached circuit board is different between models, and have different numbers of pins, but on both models, there are only three pins that actually have wires on them. on the integra, these correspond to a hot wire in, a ground wire, and the VSS signal wire to the ecu. my wagon wiring diagram sucks, and I couldn't find these wires on it.

    so the big question is, do you think I could just plug the wires in? I was under the impression that the wagon didn't have a speed sensor. also, seeing that the circuit boards are different, I'm concerned that the signal will not translate.

    thoughts?
  • here's photos of both:
  • so I was told that the entire dash harness from the integra could be substituted for the factory harness, and everything else would plug into it. this is WRONG. not even close. perhaps a different year, but not 1986.

    so now I'm working on delooming the integra harness to separate the engine management stuff from everything else and hopefully keep the splicing to a minimum. it hasn't been too hard, and I've got the ecm pretty much isolated with only a handful of wires to re-connect. vss, a couple hot wires, hazard (anyone know why the ecu is wired to the hazard fuse??) and the efi warning light.

    the problem I'm running into now is the rest of the engine-related stuff that isn't specifically necessary for EFI (starter, alternator, oil pressure sender, fan controls, a/c compressor). the best wiring diagram i could find is in a haynes manual and it's really lacking in the clarity department. I no longer have the factory engine harness so I can't just track down the wires. there are connectors that match (8-prong rectangle) between the integra and civic harnesses, but there are 2! on the civic and only one on the integra. and none of the wire colors are the same.

    I'm a little befuddled what to do next.

    anyone have a better wiring diagram on which I could track down the accessory wires?
  • the ecu is wired to the hazard fuse for the ecu's backup memory to keep trouble codes stored.
  • of course! I did think of that in the middle of the night.

    if anyone happens to have a factory engine harness for the early model lying around, I would appreciate if you could let me know the colors of the wires for the alternator, starter, oil pressure sender, and a/c pump...

    otherwise I'll have to wait for an opportunity to go back to the wrecker and look at one there.
  • you need wire colors for the '86 wagon? or for the D16A1 harness?
  • for the '86 wagon. I need to repin the rectangular plug on the d16a1 harness to match the plug on the factory civic body harness, but I don't have the d15b engine harness to work off of, and the wiring diagram I have is crap and doesn't always make the wire colors clear.
  • I'll see what I can do...give me a few days
  • I was not aware until just recently that this year wagon was originally carbureted. which explains why everyone tells me the efi harness from an integra will fit when it won't.
  • The wagons didn't get the injected engines until '88. I think only the CRX/Civic Si's of that body style got the fuel injected D15s.
  • OK, I got my ass to the picknpull and poked around to figure out the wiring. not surprisingly, the wire colors are all the same. now to re-organize them so the plugs will play nice...
  • Well...I was just about to post up the diagrams I found for the '86 wagon chassis. I'm not sure it will help but I'll post them and keep them up for a few days so you can save them if you want.

    1/6 - 1.gif

    2/6 - 2.gif

    3/6 - 3.gif

    4/6 - 4.gif

    5/6 - 5.gif

    6/6 - 6.gif

    Good luck. :)
  • sweet- thanks!!!
  • thaddeusssthaddeusss Band Wagon
    UPDATE: I've got it all in and running. here's what I had to do:

    the integra harness plugs don't match up to the carb'd civic, particularly at the gauges. I contemplated trying to find a efi wagon and trying to swap out the whole dash but it seemed like a long shot to find one. so instead I disassembled the integra harness and separated it out as cleanly as possible between the engine management stuff (ecu) and the more simple stuff (alternator, starter, oil pressure & water temp, ignition). fortunately the harnesses are put together with two separate plugs for that stuff - the round one for the ECU and the 6 or 8 prong rectangle for the basic operational stuff. (depending on A/C or not) there were two places where the ECU wires connected to the 8-prong plug, I think it was the hot-in for the starter, which goes back to the ECU, and a hot-in RUN which goes back over to the vacuum control box. the harness on my engine was non-A/C and the harness on my civic is A/C, so I made connections for those two wires when i made a 6 to 8 prong adapter plug. my goal is to keep the civic harness as intact as possible to keep troubleshooting easier and make it possible to swap back in the future if need be.

    on the dash side, the hot-in start, run, and hazard wires had to be connected for the main relay, and the fuel pump wire connected to the new fuel pump. I mounted an msd 2225 pump (came with the car) under the skid plate for the fuel tank.

    I needed a CEL so I cut the wire for the seat belt light and ran it straight to the pin @ the fuse box to bypass the timer/dinger circuit. then I moved the pin to the empty slot that corresponds to the empty light hole below the battery light. I had removed the pin for the CEL from the integra harness, and just plugged it in to the slot for the seat belt light.

    all in all it was actually fairly straightforward, but without a guide of any kind I was really doing a lot of problem-solving along the way to figure out what wires I needed and which I didn't, and where they would go and match up or not.
  • thaddeusssthaddeusss Band Wagon
    the pics below - I wanted to keep the stock airbox for the integra, so I relocated the ignition coil to the strut tower. with the vacuum control box in there, it's pretty crowded.

    there's a shot of the ECU wires going through the bulkhead. hard to fit that huge round plug through that tiny rubber boot, I had to cut it a little. practice for a future as an obstetrician :roll:
  • thaddeusssthaddeusss Band Wagon
    unfortunately, all is not perfect...
    I'm having a rough idle/ rough driving / extremely rich running problem. I have the vacuum lines all hooked up correctly with the exception of the line from the top front of the TB to the control box. I can't remember at the moment what it's supposed to be for. but when it's hooked up then the idle rises rapidly as the car warms up and within 30 seconds it's running at 4k-5k. it's kinda scary. so right now it's blocked off on both ends.

    so at the moment it's idling at ~1k but lopey, and so rich it smokes black. when i drive it, it runs great whenever I'm accelerating reasonably. it doesn't need to be hard, but at least a bit. if I'm cruising it starts to buck and miss, similar to idle but worse. I'm kinda stumped right now.
    I read somewhere that the cam timing being off can cause this - and the previous owner had put a new timing belt on. is that a possible cause?

    I know i should probably remove the IACV and clean it but haven't had the time yet. i did notice that when the engine is not running and the ignition is on, the IACV makes a constant clicking noise. is that normal?

    I don't know if it's related but the coolant temp gauge and oil light are not functional either. I haven't been able to figure out why so far. I've got no voltage @ the sender/switch for some reason. I thought it might have something to do with my unplugging the seat belt light, but they weren't working before I did that either.

    I'm continuing to plug away at it but if anyone has suggestions they would be appreciated.
  • thaddeusssthaddeusss Band Wagon
    :oops: well I pulled a stupid. when I built the jumper between the 8 and 6 prong engine plugs, I somehow mixed up the wires for the oil and temp.

    I fixed that but now I seem to have lost spark strength... it's still there but weak and it won't start. only puff once or twice on starter fluid. arrgh.
  • thaddeusssthaddeusss Band Wagon
    found out something new: there were two wagons at the wrecker - one 86 and another I didn't look at the year, but it was carbureted - one of them had the two wires I had accidentally mixed up when building my jumper harness: a yellow and a green/black. the other car didn't have them. they go to what I think is the reverse light switch on the tranny. the wiring diagram above shows the green/black going to the switch but doesn't show the yellow. anyhow, that's fixed now. but I think I burned out the oil sender switch because the light works if I ground the wire, but not if it's plugged in to the switch. oops!
  • thaddeusssthaddeusss Band Wagon
    more new sh&t, as the dude would say:

    I got a new reverse switch (it was missing) and wired it up. magically, it started again. this seems totally wrong and f*ckded up!!! I tested it and confirmed - yup, if the reverse switch is plugged in, It runs, but still poorly. if the switch is unplugged it won't start. not even on starter fluid... I can't really tell what all my problems are here, but it seems like:

    1) I get a weak spark when the reverse switch is plugged in. weak enough it won't run.

    2) I probably have a stuck or otherwise messed up IACV.

    so I need to replace the burned out oil sender, and that's pretty much impossible without removing the intake, so I'll be doing that soon - and checking out the IACV while I'm at it. crossing my fingers that will help me find the crappy rich running problem.

    the wiring issue completely confuses me. anyone have thoughts on why this might be happening? the reverse light wires as far as I can tell are YELLOW (hot from fuse box) and GREEN/BLACK (out from switch to reverse lights). I'm sure I MUST have messed up somehow wiring the ECU in, but I can't figure out how the ecu might be needing to ground out/get voltage from the reverse lights.

    any help is much appreciated!!!
  • zaccivic90zaccivic90 Band Wagon
    yep that look good
  • LayspeedLayspeed Wagonist
    That is a very strange situation. I'm pretty sure the problem is with your wiring. With all custom swap wiring, it's difficult to diagnose over the net. Retrace your ECU wiring. Maybe you looped something in a circuit somewhere? The first swap I did, I made some silly mistakes. Just needed to take a break from it and get some fresh eyes on it again. Good luck and hope you figure it out. As far as the 4-5K fast idle, I agree it's most likely a EACV/IACV issue. Something could be jammed in there. Remember, these '86-87 engines have a 'fast idle thermal valve' also on the back of the intake. On older engines, the o-ring inside dries up and flattens, then the valve's plunger seat slowly unthreads itself, creating a vacuum leak. The most noticeable symptom is a higher than normal (think 2000+) cold fast idle...and when the engine is warm, the excess vacuum can cause the idle to lope or surge back and forth between 1000-1800.
  • thaddeusssthaddeusss Band Wagon
    well, more confusion. turns out the thing with the reverse lights was a red herring.... a very convincing coincidence. I had it running today while I was working on the vacuum stuff and unplugged the wires for the reverse switch while it was running - nothing happened. glad I found out I had imagined it BEFORE digging in to find a problem that wasn't there!!

    I'm pretty much down to having a problem with the IACV. I disassembled both the IACV and the FITV yesterday and both are operating properly and not leaking. (the FITV was leaking but it was the loose-screwcap syndrome) the problem is the computer isn't closing the IACV for some reason. does anyone know the logic used to control the IACV? is it just the water temperature, or are there other signals involved? I may just have self-caused wiring issue, I'm getting a consistent code 14 from the ecu.
  • thaddeusssthaddeusss Band Wagon
    I also discovered recently that the motor mounts on the frame rails are slightly wider with the d16, and the driver side mount was pushed over enough that it was resting straight metal to metal against the frame... the whole car was vibrating something awful! it's hard to believe how much noise various body parts were making. so I disassembled the passenger side mount and ground 1/4" off of the bushing, and ground out the mounting bolts slightly so I could slide the whole mount sideways on the frame another 1/4". a torch and pry bar to the offending flange on the driver side got me the clearance I needed so it wouldn't touch anymore. what a difference!!!
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