Bootleg_integra

Having trouble finding a wiring diagram for a b20... Having a wiring issue with my 90 crx with a b20 swap

HondaPartsHero

List your trim of your CRX (Si, HF, DX, etc). In a nutshell if your CRX is DX you'll have to convert to MPFI. For Si and HF you can use that harness but if you plan on using OBD0 components (ECU, distributor, injectors, alternator) you'll have to use OBD0 components for plug and play (using integra ECU, distributor, injectors (unless Si then you can use those), and alternator). If you want to use the OBD2 components you'll have to convert all of those to OBD2 using wiring adjustments or adapters. You'll want to use an OBD1 ECU at this point for an integra. Also you'll need to wire in a 4 wire primary 02 sensor. Finally you'll have to rewire the fan switch either way as the B20 has it on the thermostat housing and your car is on the back of the block. The rest should plug and play (TPS, MAP, ECT, IAT).

capo1the8don7

i have a b20b4 swapped DA9. just wondering how i can wire the fan sensor (switch) up as i dont see a plug hanging anywhere off the harness that attaches to it.
the ca is a 1990 integra ls with a b20b4 and a p75-3 head and a 1.8 5spd

HondaPartsHero

The Integra has the plug on the back of the block, it's a different style but you can use the wires and run them to the thermostat housing of the B20. Here is what the connector looks like

https://honda-tech.com/forums/acura-...-swap-2985941/

capo1the8don7

gotcha thanks hondapartshero...your the man!