Bought a EK Hatch with B18 swap and problems

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SeVeNisOnE

Ken Korn Karn
Ok rather than make separate threads for each problem I'm going to slap them all in here. First let me describe the car.

'96 EK Hatch
B18C Block with B16 PR3-2 Head
'00 Si Transmission
Skunk2 Intake Manifold
Skunk2 Cam Gears
JG Edlebrock 65mm Throttle Body
Short Ram CAI with K&N Filter
RC 550cc Fuel Injectors
AEM Fuel Rail/Regulator
MSD Spark Plug Wires
DC Sports 4-2-1 Race Header - No Cat
A'pexi WS2 Exhaust
OBD1 P28 ECU w/Hondata S100

First problem is the engine harness. It is the original '96 DX non V-Tec harness. I'm not sure if the engine was from an OBD1 car or an OBD2 car. The head and transmission seem to be from a 99-00 Si. The Block has a B18C stamp on it. The transmission for sure is from a 2000 Si. The head has a PR3-2 stamp on it. The current ECU is a P28 with a OBD2 to OBD1 conversion harness adapter plugged in. So what do I classify as, OBD1 or OBD2? I'm just confused since I am starting to feel like the car is half OBD1 and half OBD2 and wondering what is and isn't compatible with the OBD1 ECU.

Second problem is the O2 sensor. The car has had a CEL from the beginning. I checked it and I get Code: 41 Primary oxygen sensor heater. So I bought a universal Bosch sensor and wired it up but the code is still there. I wired it up as so: the 2 OE black wires (heater) to the 2 Bosch white wires, the OE white wire (signal) to the Bosch black wire, the OE green wire (signal ground) to the Bosch gray wire. Hopefully I got it right. I was told it doesn't matter which way the heater wires are arranged as long as the colors match. The car runs the same whether the sensor is plugged in or not so I'm guessing its not working. The engine harness has two plugs for the front O2 and the rear O2, but I'm only using the front O2 plug since OBD1 ECU doesn't use a rear O2 right?

Third problem is the Speedometer isn't working. I check fuses and all are good. I checked the wires that run to the Vehicle Speed Sensor and they seem fine. I am not sure if the sensor itself is dead. Wouldn't I get a code for that as well? I guess I'll just swap out the sensor and start there.

Fourth, (I know its getting long,) I'm wondering if I should just swap out the engine harness for a 96-98 EX harness or a 99-00 Si harness since I feel like the previous owner didn't do too good a job on the harness. Almost every single sensor seems to have been spliced into the original harness. Just yesterday the car wouldn't start since a wire that connects to one of the fuel injectors came loose. took me about an hour to find the problem. OR am I able to swap in a 92-95 civic OBD1 harness? I'm not sure on this since like I said before I'm not sure if I can say the engine is OBD1 or OBD2. How can I check? This car is all Frankensteined!

Oh and another thing is there is a Injector Resistor Box installed. Do I need that? I guess I do, but can I swap injectors to get rid of it? The box is just dangling behind the head and looks ugly. Just another thing to clean out of the way.

Hopefully I didn't confuse everyone with all my problems. Please if anyone has any input on anything I listed, chime in. I need all the help I can get.
 
Ok here we go. Your car is obd2, with the conversion harness you can run any obd1 ecu but for emissions and related questions it is obd2. People convert to obd1 so that engine management can be used since obd2 ecu's are not chip able. If you want to stay obd2 then your only option is the aem standalone system which is very expensive. Second, there is no need to swap engine harnesses. Your harness is obviously fine since you are only throwing a code for o2 sensor which is no big deal. Especially since with the hondata you can shut off the code for 02 sensor. However, i think the reason your o2 is not registering is because your obd1 conversion harness probably made the secondary o2 sensor wire the primary since obd1 b series only have one o2 sensor. try pluging it into the o2 plug behind the block and see if that shuts off the code. As for the resistor box, most aftermarket injectors require one and since you are running the rc 550's you will need it. If it is hanging and looking shitty then extend the wires and mount it in a better place out of site. Good luck.
 
There is an O2 sensor plug behind the block? When I removed the sensor from where it was originally connected there are two plugs that look identical near the transmission. I tried switching the O2 between those two plugs but it still gets a Code 41. Could it be that the 2 black wires that run to the O2 heater are switched? Or does it not matter?
 
I checked the OBD1 to OBD2 conversion harness to make sure the wiring is correct for the heater element to the oxygen sensor. C7 OBD2 to D14 OBD1. Weird thing is even if I completely disconnect the O2 sensor, all I get is a CEL for code 41. Shouldn't I get other codes? Or could it be that this Bosch sensor I bought just sucks? I have a 98 Trans Am and when the OE sensors whet out on it I bought two new O2 sensors for car and it ran like crap. It would stumbple and Idle horrible. So I went and bought O2s from the dealer and the car ran like a champ. I don't know what else to do.
 
And as fot the speedometer, check the wirings see if its plugged wrong....test the volt on the speedo by jacking up your car and turn the passanger side wheel....
 
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