I am putting an ls/vtec into my 89 crx. I just recently heard that because both ecu's are obd-0 that they should just connect together, i may have to move two wires or so but the clips in my crx should connect straight to the pw0 ecu....is this true? i know becuase i am running obd-0 that all the connectors on my stock harness just connect to the engine but im not sure if the ecu's are interchangable withouth re-pinning the new clips. any help would be great.

 

As long as you are running OBD0 and your stock engine was mpfi, the PW0 will plug right in. You will only need to add wires to activate VTEC and I believe the knock sensor. I can't remember if the PW0 ecu looks for a knock sensor. If you use a PR3 ecu you will need to add wiring for VTEC, 2nd O2 sensor, and a knock sensor

 

if that is true thats exactly what i wanted to hear.

 

anyone know what the wires i have to swap are if any?

 

no swapping of wires necesaary, mostly cutting and splicing or adding a pin if there isnt one in the location.

a8 vtec solenoid- you have to add a pin.
b5 vtec pressure switch- you cut and splice
b19 knock- you splice.

c8 secondary o2 sensor- splice

 

correct above.

The only time you swap wires at the ECU is to correctly pin a DPFI wiring harness to MPFI.
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