MPFI help! 2 weeks into swap, car still not working!

i've cross-posted this on the Honda-Tech board, but perhaps there's a wagon-specific issue i'm missing:

car is a 1990 Civic wagon 2wd. did DPFI->MPFI swap. used effin guide for swap. all connections soldered and shrink-wrapped.

car cranks but won't start. car is not throwing codes at this time. was throwing a 4 due to bad connection in "b" plug.

when ignition is turned off after cranking, oil pressure and the light next to it (door open? hatch open? i can't remember) are dimly lit. the seatbelt light is very dimly lit - can barely see it. and the ecu blinks randomly. this continues until one of three things happens: 1. disconnect battery. lights and ecu stay off after reconnect. 2. unplug main relay. they stay off after reconnect. 3. randomly turn off on their own.

with key on, have no power out from main relay to injectors or fuel pump. main relay is new - as in, replaced it and the problem persisted.

fuse 14 has continuity and power. fuse 37 has continuity and power.

to check wiring harness to main relay, manual states that yellow/black wire going into main relay should have power with the ignition off. mine does not. fuse 14, which supposedly powers the blk/yel input, appears to be switched. this is according to the wiring diagrams i have and empirical testing.

turning ignition to "on," hear the characteristic "click-click" from the main relay. again, no power to fuel pump or injectors. or out from relay.

relay has continuity to ground through black wire and to ecu pins A12/A14 through blk/grn wire. ecu has continuity to ground through both A2 and A4.

ELD checks good.

two different (one known good) ecus have been tried, no change in symptoms.

main relay has been replaced.

fuse box has been dissasembled and cleaned.

ignition switch has been resoldered, dissasembled and cleaned.

has anybody got any ideas? or should i just splice in a switch and relay to supply power to the fuel system? or will this even work? i'm bloody stumped at this point.

also, car ran fine before swap, other than occasional refusals to crank. when bypassed at starter signal connector, always started.

:?

Comments

  • SiWagonSiWagon Council Member
    :? Pull fuse #14.Check for voltage there.Also check fuse for continuity.

    Was ECU for a manual & is your Wgn. a manual?
  • HaydzHaydz Moderator
    jhota wrote:
    fuse 14 has continuity and power. fuse 37 has continuity and power.
  • turbo_tegturbo_teg Council Member
    u can use a simple light tester to see if your injectors are getting power and signal. clip the end of the tester to the negative battery post then stuff the probe into all 8 wires for the injectors 1 of the 2 wires for each injector should be a constant power while the key is ON. then hook the tester to the positive cable and stuff the probe into the 4 wires that didnt have constant power from the first test. your test light should flicker on and off that is the point when your injector should be clicking on and off. hope this helps but this is my guess on whats wrong with the whole swap u did and all. GL let us know what happens!!!
  • it LIVES!

    has a set of issues screwing me up:

    poor grounds. the connections themselves were o.k., and the wires show continuity, but resistance was a bit high. so i ran additional ground leads directly from the negative terminal (i love aftermarket battery terminal clamps, btw) to critical grounds.

    that fixed the fuel pump and injector pulse issues.

    all four injectors were clogged solid. ordered a set from Linder Technical Services (highly recommended, btw! replacement injectors $25 each with a $5 core, very fast service), replaced the baddies, and the car started.

    no CELs because i'd already been through everything multiple times, of course.

    and the bizzare stuff staying on and bleeding power back through the circut, with random ecu flashing?

    the automatic seat belt control unit is buggered.

    well, i needed to get off my ass and install a roll bar and proper harnesses anyway, right? so that's the next project.

    when i get some time, i'll post pics in the rides section, both before and after, etc.
  • and it's dead again. died on the interstate on the way in to school this morning. (actually posting this during class, fwiw...)

    guy i used to work with saw me broken down and gave me a lift.

    cranks, but only pops and snorts like it's dumping raw gas through the engine - doesn't really fire. fuel was burning in the exhaust, not the motor. the pipes were hot (had been running for 1/2 an hour), so that's not a surprise.

    have to check for spark when i get home, i guess.

    it's also throwing a Code 20, no CEL.

    argh.
  • turbo_tegturbo_teg Council Member
    code 20 Electrical load detector.
  • yeah, i know what code 20 is. i even know why it's throwing it. i just don't know why it's doing what it is to throw it. yet.

    i suspect that, since it was pouring rain this morning, something got wet that shouldn't have.

  • jhota,

    did you ever get this resolved?
  • yeah. it decided to throw the set screw out of the rotor button. no spinny rotor, no spark to cylinders, no run = code 20.

    new cap and rotor, all better.
  • yeah. it decided to throw the set screw out of the rotor button. no spinny rotor, no spark to cylinders, no run = code 20.

    new cap and rotor, all better.


    great!
    so how does it run now?
    is the throttle response faster? feel any difference?

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