weird civic problem :(

OneSweetWagonOneSweetWagon Band Wagon
in Engine & Drivetrain
So I just finished my mpfi swap on my 89 d15b2 and it idled bad at first and I found a few air leaks and fixed them. Still ran kind of bad then it magically started running fine. I drove it to work (40 mi) and it ran like a champ but when I went out to start it after work it just cranked and cranked but wouldn't turn over. I let it sit for a while and I finally got it to turn over but I had to stay on the gas a little bit. After it started the idle surged between 2.5k and 3k rapidly but stuttered hard in between shifts. Then after a few minutes it started running fine again. I was thinking maybe a faulty sensor or something but it has been so sporadic. I need help!!!

Comments

  • bikewrenchbikewrench Wagonist
    try checking your FITV (if you have one). it would be under the throttle body. it is supposed to let air around the throttle plate when the engine is cold so it will idle higher. sometimes they become a vacume leak. Google civic fitv.
  • VIPwryannVIPwryann Wagonist
    If it ran very well to start I would go over all your work, then maybe check for vacuum leaks
  • crxedcrxed Band Wagon
    bikewrench wrote:
    try checking your FITV (if you have one). it would be under the throttle body. it is supposed to let air around the throttle plate when the engine is cold so it will idle higher. sometimes they become a vacume leak. Google civic fitv.
    It's called EACV
  • OneSweetWagonOneSweetWagon Band Wagon
    I plugged the fitv hole (intake didn't have one on it when I got it) and I will have to check the eacv. The car seems to be sucking fuel too. Maybe an fpr, o2 sensor, map sensor or something else? It had the roving idle before the mpfi swap but I thought it had something to do with the shitty dpfi system.
  • OneSweetWagonOneSweetWagon Band Wagon
    I plugged the fitv hole (intake didn't have one on it when I got it) and I will have to check the eacv. The car seems to be sucking fuel too. Maybe an fpr, o2 sensor, map sensor or something else? It had the roving idle before the mpfi swap but I thought it had something to do with the shitty dpfi system.
  • bikewrenchbikewrench Wagonist
    FITV=fast idle thermal valve
    IACV (not EACV)=idle air control valve

    2 different things
  • crxedcrxed Band Wagon
    bikewrench wrote:
    FITV=fast idle thermal valve
    IACV (not EACV)=idle air control valve

    2 different things
    I didin't think pre-92 Honda engines had a FITV
    Same goes for EACV (pre-92) and IACV (from 92)
  • bikewrenchbikewrench Wagonist
    You're probably right. I'm more familiar with the obd1 engines. The only obd0 engine I've worked on is the A6 I pulled from my wagon, and it doesn't have a fitv. I have had 2 obd1 cars that have had bad idle problems and it turned out to be the fitv both times.

    onesweetwagon, are you using the a6 intake manifold for your swap?
  • OneSweetWagonOneSweetWagon Band Wagon
    yes I believe it is an a6 manifold (91 crx si). The car is running rich and doesn't seem to have as much power as it should. A few things I am concerned about: using dx fuel line and throttle cable (they seem to fit fine though), unknown fuel pressure regulator (I had to get this separately as the manifold didn't come with one)
  • AintGotNoSolAintGotNoSol Wagonist
    crxed wrote:
    bikewrench wrote:
    FITV=fast idle thermal valve
    IACV (not EACV)=idle air control valve

    2 different things
    I didin't think pre-92 Honda engines had a FITV
    Same goes for EACV (pre-92) and IACV (from 92)

    Yeah, the Civic Si/EX / CRX Si / Wagon RT4WD engines (D16A6) DID have an FITV. It works differently that 92-95 units though. 92-95's use a coolant feed with a temp-controlled valve, while the 88-91 A6 units were electrical. Dude said he's using the CRX Si manifold, so it's supposed to have it. Sounds like his is missing though, and he plugged up the holes. Could be part of the problem. Sounds kinda like he has multiple problems.

    I do not know if the D15B2 DPFI motors had one or not. I imagine they had some form of it, but I never came across it.

    OP, remember to check all your grounds!!! Particularly the one that bolts to the thermostat housing.
  • CleanpigpenCleanpigpen Band Wagon
    AintGotNoSol wrote:
    crxed wrote:
    bikewrench wrote:
    FITV=fast idle thermal valve
    IACV (not EACV)=idle air control valve

    2 different things
    I didin't think pre-92 Honda engines had a FITV
    Same goes for EACV (pre-92) and IACV (from 92)

    Yeah, the Civic Si/EX / CRX Si / Wagon RT4WD engines (D16A6) DID have an FITV. It works differently that 92-95 units though. 92-95's use a coolant feed with a temp-controlled valve, while the 88-91 A6 units were electrical. Dude said he's using the CRX Si manifold, so it's supposed to have it. Sounds like his is missing though, and he plugged up the holes. Could be part of the problem. Sounds kinda like he has multiple problems.

    I do not know if the D15B2 DPFI motors had one or not. I imagine they had some form of it, but I never came across it.

    OP, remember to check all your grounds!!! Particularly the one that bolts to the thermostat housing.

    D15B6 and B2 don't have one. It may also show up in a Service manual as FICSV Fast Idle Control Solenoid Valve. Quite redundant if you ask me.
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