So as we know they come with the low-port SR20DE...

OBD II began in 1995...

So that means it has the standard B13 OBD I ECU...

But what about sensors. Does it use highport coolant temp sensors, or lowport coolant temp sensor? Gauge temp?

Really what I am trying to figure out, is how different is engine management from 91-93 compared to 94.

Thanks guys.

:-) Don't know enuff here. My '93 had, of all things, a '94 lowport in it (long story, but the high port had been toasted before I got it. It had the '93 ecu in it. When I sent that off to Miko to get one of his jwt ve ecus, I got an ecu out of a '94 G20 automatic. Car ran LOADS better for the month before I started the swap. You SHOULD be able to interchange the sending units that screw in to the water manifold under the passenger side end of the intake. The two pin piece goes to the ecu, the single pin piece closer to the block is for the "gauge" on the dash.

The only differences in engine management between the '94 and the '91 - '93, are the '94 had EGR temp and no AIV. The coolant temp sensors are the same. I used a '94 ECU in my '91, and everything worked. I'm pretty sure the B14 sensors are the same, but I've never looked at both side by side. The '94 motor also uses the same oil filters as the '91 - '93.