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B18C swap p0171

Discussion in 'HYBRID -> EG-EK / DC' started by doEKi, Oct 6, 2012.

  1. doEKi

    doEKi New Member

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    Hello, new to this site but not to civic's yet I have come to a real puzzler.

    I used to have an obd2 h22a4 swap and now i have a obd2 b18c swap that I bought off a friend.

    The block is stamped b18c but the head is stamped p72. As far as I know I have a b18c mixandmatch. Transmission is an S80 LSD.

    Here is where I get stumped I took it in to my mechanic and he couldnt figure it out. He said both oxygen sensor are working as they should be. Fuel pressure is normal. Map sensor was ok. Ignition timing and valve lash ok.

    Before I took it in I replaced the cap/rotor, fuel pump(from 99 civic) and ran seafoam through the gas tank.


    The only thing I can suspect are the injectors. My mechanic speculated the ecu but I dont think its the ecu (p73 ecu).

    I asked my friend who sold it to me and said i must have wired something wrong. But I checked and rechecked all of the sensor wiring and cant find anything.

    Also, originally he was running his setup with injectors and a resistor box, he kept those and gave me 4 other injectors that he said came off a 00 civic si. He said they are all the same flow rate.

    Is this ture?



    Thank you
     
  2. doEKi

    doEKi New Member

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    I made a mistake the injectors he included were from an 00 civic vtec engine.

    Also my civic is a 1996 lx sedan.

    Other mods include AEM cold air intake, Mishimoto thermostat, Mishimoto radiator, DC exhaust head, and aftermarket exhaust

    Engine bay and interior are mostly gutted
     
  3. E_SolSi

    E_SolSi Member of the 20 nut club Moderator VIP

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    yes they are the same injectors

    your issue is most likely a vacuum leak
     
  4. doEKi

    doEKi New Member

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    That was the first think i checked for. I couldn't find anything. And I didn't ask the mechanic if he smoke checked it.

    I do have a vacuum gauge and at idle it stays around 20 inches Hg.

    The weird part is that it will "stumble" vacuum goes down and then back up to steady 20"Hg.

    I do have an obd2 scanner and when it "stumbles/shakes" the fuel trims drop but then start to go back up.
     
  5. doEKi

    doEKi New Member

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    I went around the engine today, checked for loose vacuum connections and sprayed the intake, manifold, throttle body, evap system with soapy water and there was no change in idle.

    I dont know what the heck to do now
     
  6. doEKi

    doEKi New Member

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    I tried the stock intake to no avail.

    I removed the IACV and cleaned it out, was cleaner than I expected. Re-installed and set the idle. That all went ok. I checked the intake manifold bolts/nuts, exhaust manifold bolts and spark plugs but all were nice and tight.

    Checked the PCV valve and I could hear it rattle as I shook it.
    Rubber grommet/seal around the oil dip stick was in one piece.

    BUT. On the intake manifold I did find a capped vacuum tip. I cant get the cap to come off but also I don't see any vacuum line going to this in the manual.

    The vacuum tip (facing from front) is towards the bottom rear right of the manifold. I will try to post a picture.
     
  7. doEKi

    doEKi New Member

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  8. doEKi

    doEKi New Member

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    What if the mechanic was right what if I need a different ecu.
    But I figured that the usdm p73 would work fine on the b18c

    How would I know, I can't currently find any to borrow and purchasing a new one is out of the question momentarily.
     
  9. doEKi

    doEKi New Member

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    I checked wiring again today. With the scanner today i could see the map,tps,ect,oxygen sensor working fine.

    I feel like its useless......but there has to be a way
     
  10. Briansol

    Briansol Admins Admin VIP

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    p73 is from the itr. p72 is the gsr/sir-g.

    I can't see pics (work filter). Is it a gsr or type r style? (intake manifold, does it fold up, or down?)
    pump/injectors should be fine to support either. all b series injectors are 240cc.

    So, if your fuel system is too lean, perhaps there is a clogged fuel filter?
    Or, the o2 is shot/gummed up.
    have you tried a new o2 sensor?
    do you have access to a wideband to verify that it's too lean?
    is the ecu chipped? my understanding is that p73s are keyed with immobilizers and are basically impossible to use unless you have the matching ignition set.
     
  11. doEKi

    doEKi New Member

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    Thanks for the response
    I believe that manifold is the type r style.
    Also the primary oxygen sensor was replaced during the swap, secondary was replaced as well but a few weeks earlier along with the fuel filter.
    I don't have a wide and currently just the scanner where I can see the fuel trims going up to 46.9% for short term.
    I used to have a chipped ecu and it would not connect to the scanner where this one does.
    And I had no clue about a imobilizer, it turns on ok.

    It does stumble a bit though when it's cold
     
  12. doEKi

    doEKi New Member

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    So the p73 ecu won't work on this engine?

    I'm going to inspect it today and try to find out what engine I really have

    Block is stamped b18c and right underneath is a serial #
    Tranny is s80/LSD
    Head is p72
    Ecu: p73
     
  13. Briansol

    Briansol Admins Admin VIP

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    Well, it will work fuel/etc wise, but it shouldn't turn the car on due to the immobilizer. Is it a jdm ecu? (small case)
     
  14. doEKi

    doEKi New Member

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    It's P73-A03 with a WB on the bottom right. Which I believe is usdm
    The car does turn on and idles ok,, just at times it coughs/stutters and rpm drops I think its misfiring
     
  15. doEKi

    doEKi New Member

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    Since the block is stamped B18C with a serial number beneath it, the head is stamped P72 then I am assuming I have a USDM GSR.

    So I guess I need to start looking for a USDM P72
     
  16. CAFROG

    CAFROG Honda Minion VIP

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    That plugged nipple is (to the best of my knowledge) the vacuum line for the evap purge solenoid. My B16A3 was in te same exact spot. USDM ECU's look for the evap purge (USDM engine harnesses have a plug for it) but I know my JDM P30 ECU didn't need or have one. But....I don't think this is a real issue

    The intake manifold looks nothing like a GSR IM. You say it's ITR style....does that mean its aftermarket? Must be with a P72 head.

    My best guess.....after reading the things you did.....it's something with the injectors and the switch over that occurred. I would look more into the schematics for the injection system and check the wiring more.
     
  17. doEKi

    doEKi New Member

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    What iv'e got so far(mostly from wikipedia):

    USDM

    B18C1 1994–2001 USDM Integra GS-R (DC2/DB8)
    ECU: ¿ P72-A03 ?

    B18B1 1994–2001 Honda Integra "RS/LS/GS/SE" (DC4/DB7)
    ECU: ¿ P75 ?

    B18C5 USDM DC2 Acura Integra Type-R (Integra Type-R)
    ECU: ¿ P73-A03 ?

    JDM

    B18C 95-00 JDM Honda Integra Type R DC2; 95-00 JDM Honda Integra Type R DB8
    ECU: P73-003 (96spec R) P73-013 (98spec R)

    B18C 95-98 JDM Honda Integra SiR/SiR II (DB8, DC2); 98-99 JDM Honda Integra SiRG (DB8, DC2)
    ECU: P72


    But the B18C1 utilizing the P72 ECU requires to my understanding a IAB control diaphragm valve, IAB control solenoid valve and also is a completely different looking manifold than the one I have

    And the p75 is non-vtec I believe so I can't use that ECU either. So in reality am I not only left with using the P73?
     
  18. doEKi

    doEKi New Member

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    I am utilizing the EVAP purge solenoid valve yet on my set up it is connected in an outlet on the throttle body for vacuum source instead of that capped nipple.

    I cant find any P73 stamp on the intake manifold which does lead me to believe that it is an aftermarket piece.., correct on the P72 head.

    I will look at them stringently again and hopefully you are correct.

    Thank you
     
  19. doEKi

    doEKi New Member

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    Sorry about the low lighting but I am using my phone and flashlight.

    [​IMG]

    That is where the vacuum source for the Evap solenoid is

    I looked over the wiring and from cylinder one to four the orders of the wires (+) are brown, red, blue and yellow each with its own respective ground.

    I traced the wires and all were well connected/spliced into the harness.

    As soon as I get a chance I will run a continuity check from those four (+) from the ECU harness to the injector plugs and make sure there all ok.

    If I remember correctly a few weeks ago I checked the injector plugs and at each (+) pin of the connecter with the key on engine off I believe it read battery voltage, as I think it should.
     
  20. Briansol

    Briansol Admins Admin VIP

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    The IAB will throw a code if not plugged in on a p72, but it won't effect performance or throw it into limp mode. With a chip, it's easily defeated.
     
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