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Discussion Starter · #1 ·
I got my adapter harness for an OBD1 conversion done, going to do the dizzy wires later today (why have a y8 with no VTEC?!). What do I do with the resistor box for the injectors? I also scored a Nokia data cable for free, so I'm going to try to get that in tonight too.
 

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If you are running your A6 injectors you need to just leave the resistor box as it is. If you are swapping out to newer injectors you need to remove the resistor box and tie all the grounds together. I say, just leave it that way it is.

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d16z6rex said:
tie all the grounds together.
The resistor box connections are power, not ground... The ECU has the ground side of each injector. If you tie the resistor wires together and ground them, you'll blow a fuse or fry your main relay. Just connect the 5 wires together, bypassing the resistor box.
 

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Discussion Starter · #4 ·
Ok, so I'll leave the resistor box for now until I get some OBD1 injectors. My next question is about the VTEC... I just hook it up to the single wire coming out of the solenoid? There's another plug there that's identical to the coolant temp sensor plug under the dizzy, do I want to do anything with that or just leave it alone? Also, is the Y8 head supposed to have a coolant bleed valve? Mine has the spot where it would go, but the hole is blocked at the bottom and there aren't any threads. I suppose I could take the one off my A6 head if I really need it. Once I get the timing set right and run the thing off the PM6, I'm going to try the harness, hopefully I'll be running VTEC by the end of the day!
 

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why swap to obd1 injectors? just leave yours.

sorry i misstated what you do with the resistor box...i wasnt hinking straight. the resistor box can be thought of as a 4 pack of resistors. so just bypass it if you want to run obd1 injectors. but hey, if what you have now works dont touch it.

he made his conversion harness from plugs of one of my old dx ECUs.

leave that other plug alone on teh vtec solenoid, you just need that one wire connected to make it work.

dont know about the coolant bleed valve...

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Discussion Starter · #7 ·
bittles110 said:
Did you make your own conversion harness? Or buy one?

I'm still trying to piece together my kit before I put it all on, and am wondering how others have done it.
I made one. Get a broken or useless OBD0 ECU, and get the ECU plugs from an OBD1 car. When I got my P28 from a junkyard, I cut a length of harness to go with it, and used the female plugs from a PM5 ECU (OBD0 DX I believe). Take apart the DX ECU and desolder the plugs, then just solder the wires from the OBD1 harness to the appropriate plugs. You'll have a few wires left over, you will have to run those separately.
 

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Huh... I guess that's how the conversion harness people do it, but I hardwired mine - Cut off the ECU plugs and solder on the OBD-1 connectors in it's place. It's one less set of connector pins to fail.
If you're using a P28, the ECU will complain about the missing VTEC pressure switch (the 2 pin connector on the solenoid assembly) if you don't hook it up. One side gets grounded, the other goes to the ECU... It should be an org/blu wire.
As for the coolant bleeder, it wouldn't hurt. I swapped the stock radiator outlet from my last motor so it would point in the right direction. Worked fine with a 'Z6, I'm not sure about the Y8.
 

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Discussion Starter · #10 ·
bobski said:
Huh... I guess that's how the conversion harness people do it, but I hardwired mine - Cut off the ECU plugs and solder on the OBD-1 connectors in it's place. It's one less set of connector pins to fail.
If you're using a P28, the ECU will complain about the missing VTEC pressure switch (the 2 pin connector on the solenoid assembly) if you don't hook it up. One side gets grounded, the other goes to the ECU... It should be an org/blu wire.
As for the coolant bleeder, it wouldn't hurt. I swapped the stock radiator outlet from my last motor so it would point in the right direction. Worked fine with a 'Z6, I'm not sure about the Y8.
I don't really like cutting up stock harnesses, and it's starting to look like I may be selling my CRX this summer (to get another, don't worry), so I want to be able to take my OBD1 stuff out of it. I may swap the coolant bleeder, though I allready cut my upper radiator hose to fit the Y8.
 

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Sort of a dead post, but should be helpful if my attempt of a write up goes well.

downest: did you happen to take any pictures of your conversion harness? And where did you get the pinouts from? Any tips on making my harness? I picked up the male plugs from a ODB0 PM5, and some random OBD1 females with 10 inches of wire... are all OBD1 harnesses the same?
 

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Discussion Starter · #12 ·
That's what I did, I can snap a pic for you if you like. This is the conversion guide I used, found it on HT:
OBD0 - Function --> OBD1 - Function
A01 - INJ #1 --> A01 - INJ #1
A02 - PG1 --> A23 - PG1
A03 - INJ #2 --> A03 - INJ #2
A04 - PG2 --> A24 - PG2
A05 - INJ #3 --> A05 - INJ #3
A06 - PCS --> A20 - PCS
A07 - INJ #4 --> A02 - INJ #4
A08 - LOCKSOL --> XXXXXXXXXXX
A09 - NOTUSED--> XXXXXXXXXXXX
A10 - EGR CSV--> A11
A11 - IACV --> A09 - IACV
A12 - FLR1 --> A07 - FLR1
A13 - IGP1 --> A25 - IGP1
A14 - FLR2 --> A08 - FLR2
A15 - IGP2 --> B01 - IGP2
A16 - GRD --> A26 - LG1
A17 - NOTUSED--> XXXXXXXXXXXX
A18 - GRD --> B02 - LG2
B01 - VBP --> D01 - VBU
B02 - NOTUSED--> XXXXXXXXXXXX
B03 - ACC --> A15 - ACC
B04 - FANC --> A12 - FANC
B05 - ALT --> A16 - ALT
B06 - MIL --> A13 - MIL
B07 - NOTUSED--> XXXXXXXXXXXX
B08 - ACS --> B05 - ACS
B09 - NOTUSED--> XXXXXXXXXXXX
B10 - CYP P --> B11 - CYP P
B11 - FUSEBOX--> xxxxxxxxxxxx
B12 - CYP M --> B12 - CYP M
B13 - FUSEBOX--> B09 - STARTER
B14 - ALT --> D09 - ALT
B15 - Igniti --> A21 - ICM
B16 - VSS --> B10 - VSS
B17 - Igniti --> A22 - ICM
B18 - NOTUSED--> XXXXXXXXXXXX
B19 - ELD --> D10 - ELD
B20 - SCS --> D04 - SCS
C01 - CKP P --> B15 - CKP P
C02 - CKP M --> B16 - CKP M
C03 - TDC P --> B13 - TDC P
C04 - TDC M --> B14 - TDC M
C05 - IAT --> D15 - IAT
C06 - ECT --> D13 - ECT
C07 - TPS --> D11 - TPS
C08 - EGR VLS--> D12
C09 - PA --> NOTUSEDXXXXX
C10 - BKSW --> D02 - BKSW
C11 - MILGRND--> D17 - MAP
C12 - SG2 --> D22 - SG2
C13 - VCC1 --> D19 - VCC1
C14 - SG1 --> D21 - SG1
C15 - VCC2 --> D20 - VCC2
C16 - O2S --> D14 - PHO2S
 
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