I'm helping this lady do just a replacement engine in her integra. The original motor is a 96 (obd2) b18b1 and the replacement is a 93 (OBD1) b18b1 from the motherland. I'm swapping over the obd2 harness, intake manifold, and distributor. Anything else I may need to make everything go smooth and no check engine light? I heard from a friend I have to swap over the crank angle sensor from the original engine too--is this necessary? Anything else I forgot?

 

obd2 ls ecu, i have one if you need it

 

The original engine was an OBD2 B18b1, so that means I don't need to change out the ecu .
Anyone else?

 

You will need to swap over the oil pump, as the crank fluctuation sensor is mounted to special fittings which are cast into the pump. You will also need to swap the upper rad hose neck from the 96 motor onto the 93 motor, as the rad fan switch is in the rad neck on the 96, and in the back of the block on the 93. You should probably swap the injectors and the distributor over as well. The plugs on the 93 stuff won't plug into the 96 harness.

 

If the oil pump are required in order for the crank angle sensor to be bolted up, can I just leave it as is and tie the sensor somewhere outside the obd1 timing cover and just plug in the sensor to the obd2 harness? I can't swap over the oil pump from the old engine because it's messed up. The old oil pump was the root of the spun bearing in the old engine. Any suggestions to my scenario?

 

The OBD2 ecu won't run properly without the crank fluctuation sensor properly mounted and operating. You will get a CEL (check engine light) and the ECU will store a code. You may be able to take apart the OBD1, and OBD2 oil pumps, and use the insides of the OBD1 pump in the OBD2 housing, but chances are that the OBD2 pump housing is fubared as well, and you'll need a new complete oil pump.

And I nearly forgot, but you need to use the crank pulley for the timing belt from the OBD2 motor, because it has teeth integrated into it for the crank fluctuation sensor to read the crank position.