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d15b in my crx

Discussion in 'HYBRID -> ED-EF / DA' started by 91REXsi, Oct 8, 2007.

  1. 91REXsi

    91REXsi New Member

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    I swapped my new d15b motor into my 91 CRX si. Most all of the wiring seems pretty self explanatory, but I had a few questions. The intake manifold seems quite different. My old manifold had eletrical 3 plugs going to it. One was towards the throttle body and I think its an air valve or something. The second plug goes to a canister towards the drivers side of the manifold, it looks like a pressure sensor or something, the wires going to this are blue and black I believe. The last plug has red and green wires coming from a white plug. My new manifold only has the white plug with green wires and the air valve plug towards the throttle body... My second question was regarding the vacuum lines coming from the map sensor on my firewall. There are two vacuum lines that used to plug into my intake manifold, but there are no plugs in the new manifold. Is this because the map sensor is relocated on the new engine? Finally, I had a question about o2 sensors. My engine came with a 1 wire o2 sensor. My wiring harness adapter supports a 4 wire o2 sensor. I've read that the P-08 ECU can use either a one or four wire o2 sensor... will this work? can I just splice the o2 sensor wire into the signal wire of the harness?

    Thats it for now, but i'm sure ill have more questions so stay tuned
    thanks
     
  2. 91REXsi

    91REXsi New Member

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    My old engine had two wires running to a sensor on the back of the block, my new motor didn't have this. I spliced these wires into the plug on the thermostat of the new engine. The wires were the same color, but I just wanted to check to make sure this was the right move.
     
  3. 91REXsi

    91REXsi New Member

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    anybody?

    The plug on the old manifold that isnt on the new one is apparently for the FITV. Does the d15b intake have a FITV? is it relocaed somewhere else?

    second, where's the coolant temperature sensor plug located on my wiring harness? Is it in the same bundle as the o2 sensor?

    thanks
     
  4. jlicrx

    jlicrx Senior Member

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    your Si had a fast idle control valve on the back of the intake manifold close to the driver's side - the D15B doesn't have the FICV - it has a fast idle thermal valve on the bottom of the throttle body

    the white connector is the Intake Air Temp sensor on both manifolds - has 2-wire connector with red with yellow stripe and green with white stripe wires

    the part on the back of the manifold toward the throttle body is the Electronic Air Control Valve (EACV) - has 2-wire connector with blue with yellow stripe and black with yellow stripe wires

    the MAP sensor was on the firewall on your Si - it is on top of the throttle body on the D15 - you need to unplug the connector from the MAP on the firewall and connect it to the MAP on the throttle body - the wires may not reach - you can try freeing them up a little on the inside of the car where they go through the firewall - if you can't get enough slack, you will have to add a short pice of wire to each of the three wires

    the other vacuum line from the Si engine to the firewall (besides the MAP) was for the purge cutoff solenoid valve which is located just to the right of the MAP sensor - the JDM engines didn't use a purge system so there is no place to run the vacuum hose to on the manifold - you can put a tee into the vacuum line that runs from the front of the manifold to the fuel pressure regulator and pick up the vacuum there

    your Si had the cooling fan switch on the back of the block next to the oil filter - on the OBD1 engines it is located on the thermostat housing - sounds like you have it wired up right

    the connector for the ECU coolant temp sensor (2-wire with red/white and green/white wires) should be right next to the connector for the temp gauge (1-wire, yellow/green) - should be on the same branch of the engine harness as the distributor connectors, right next to the O2 sensor and the wires to the back-up light switch on the transmission

    yes, you can run the 1-wire O2 sensor - the other wires on the 4-wire are for the heated part of the O2 sensor - JDM cars didn't have 4-wire O2 - just use the signal wire or swap in your 1-wire O2 sensor from your Si
    __________________
     
  5. 91REXsi

    91REXsi New Member

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    wow, thanks for the great response. I figured most of that out on my own in the past few days, but thanks alot for such a complete answer.

    I ran into one more issue... There are two grounds that come off of the negative terminal of the battery. One goes to the body of the car, but where does the other one go? I assume it goes to the engine or tranny, but I cant remember where.

    thanks
     
  6. jlicrx

    jlicrx Senior Member

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    it bolts onto the bracket holding the clutch cable on the transmission
     
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