Help Awd Wagon Coverted to 2wd!

JosecivicwagonJosecivicwagon New Wagonist
in Engine & Drivetrain
Hi guys wanted to see you you guys can help me out i own an awd civic wagon 89 automatic and my transmission went out? Needed a new awd tranny but was not able to find one. It was easier to get a 2wd tranny.

So my buddy did the conversion we took the drive train out needed new axles shift linkage and even put a 91 civic ecu.

Now my problem is when i drive the wagon now a s4 green flashing light doesnt come off

and i feel like it doesnt shift to the last gear because when im driving at 65mph feel like its reving hight its about 3-3.5 rpm

ALSO WHEN I DRIVE 80 ITS A 4RMP WAS IT SUPPOSE TO SHIFT TO DRIVE AT LOWE RPM

do any of you know if it a sensor or something? Has it been done?

Thank you

Comments

  • CharbCharb Administrator
    Well, I can't answer your full question, but I can say that my old manual RT did 3k rpm at 60mph.

    So, that doesn't sound too bad. But I don't know where you were at (rpm wise) beforehand.

    Good luck!
  • JosecivicwagonJosecivicwagon New Wagonist
    oh kool do you know how many gears it has? feel like it only shifts 3 times now?

    thanks alot
  • RTiAWDRTiAWD Band Wagon
    I believe the autos for the wagons are only 4 speeds
  • JosecivicwagonJosecivicwagon New Wagonist
    oh kool so the 3 types it shifts is 4rd gear?
  • RTiAWDRTiAWD Band Wagon
    yea that would be correct
  • JosecivicwagonJosecivicwagon New Wagonist
    koo do you know if the s4 greenlight flashing would mean anythng or its because it was converted form awd auto to 2wd auto?
  • JakerJaker familEE
    Is the 91 Civic ECU that you used an Auto ECU? If not, that would explain the flashing S4 light, and your torque converter isn't locking either so the engine is probably revving higher than it should at highway speeds. It'll make for worse fuel economy as well.

    The code on the ECU should be 37820-PS9-XXX. The last 3 digits are less important than the middle 3. If your's says 37820-PM6-XXX, it's for a manual, and that's the issue here.

    Why did you change the ECU anyways? The one from your 89 should work fine. The shifting internals of the 2WD transmission are essentially the same as the 4WD as far as the ECU is concerned.
  • JosecivicwagonJosecivicwagon New Wagonist
    kool thanks for the info i think it is a manual ecu but even with when it had the original awd ecu it would flash?(tilll have it)
    so ur saying to get a 2wd ecu?

    and what do you mean the torque converted? how do i fix revving

    with new ecu would reving come down and what kind of ecu would work

    thank you
    appreciate help
  • JakerJaker familEE
    The torque converter is the interface between your transmission and the engine. It lets your engine idle when your at a stop without staling the engine, and does some torque multiplication at lower speeds to help acceleration. It's basically a slipper clutch, just a really sophisticated one. Every automatic transmission car/truck has one. If it doesn't lock at highway speeds (something that is controlled by the ECU), it continues to slip, and some of the engine's power (and fuel economy) is wasted.

    If you want more info about them, try Wikipedia. There's tons of info about it. As far as the flashing S4 light, I'm not really sure why it's doing that. What was the model code on your 89 ECU?
  • JosecivicwagonJosecivicwagon New Wagonist
    thanks alot

    should i put original 4wd ecu? flashing s4 is still going to flash

    and put a new cluster since the awd wagon cluster is different then the 2wd wagon
    and doesnt have the same options like the s4 light

    also might the 2wd tranny i got be bad since its slips and revs high? whats the correct 2wd tranny to get?

    thank you again
  • JakerJaker familEE
    The flashing S4 means there's something wrong. Did the engine rev too high with the 4WD transmission and the 89 ECU in it? Maybe the wiring to the torque converter solenoid from the ECU was unplugged or damaged all along?
  • JosecivicwagonJosecivicwagon New Wagonist
    when i had the awd tranny everything works perfect

    i just cant figure out why the s4 light dont come off
  • JosecivicwagonJosecivicwagon New Wagonist
    so it should NOT flash even if i put the 2wd tranny and original awd ecu

    any clues how to fix?

    thanks really frustrated with it and the high revving at high mph like 80
  • JakerJaker familEE
    Make sure the plug to the torque converter solenoid is plugged in, and if it is, make sure the wiring back to the ECU is not damaged. Put the 89 ECU back in. What's the code on your 89 ECU?
  • JosecivicwagonJosecivicwagon New Wagonist
    damm need to take out the one it has on but the one i have on my hand it pretty sure its the original one that i took out says
    37820-pm6-a510
  • JosecivicwagonJosecivicwagon New Wagonist
    if i put 37820-PS9-XXX ecu will it work?
  • JakerJaker familEE
    The PM6-A51 is actually an auto ECU as well. Try that one.
  • JosecivicwagonJosecivicwagon New Wagonist
    need to find one but wjen i do i will update

    hopefully it is the ecu

    and everythings works after

    but anyone that knows anythng else about the conversion
    would apreciate the help
  • JosecivicwagonJosecivicwagon New Wagonist
    hey jacker
    so i got a new ecu auto 2wd from a crx hf a mp8 multi injection
    and the s4 is still flashing
    i finaly go what you said about the silinoid
    well wen i had the awd tranny it had like 2 silinoids
    so now that i converted it it has one and i conected one conection but it has like another connection
    just there no where to connect?
    so a came to a conclusion
    maybe i need a new wire harness that connects all the way form tranny to ecu or
    any ideas?
  • JosecivicwagonJosecivicwagon New Wagonist
    also how can i check if the wiring from torque converter silinoid to ecu is damaged or not?
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