car: 98 civic cx swap: b18c5 harness used: 99-00 civic si and obd2B to obd1 conversion harness ecu: p06 for temp use until i get a p28 with a chip to tune. problem: speedo and tach does not work. car starts up and runs. i did not drive the car much after the swap. just took it from the shop to my house. heres some info i found in a link: "The 99-00 Si engine harness looks the same as the 96-98 but the ecu plugs are different and the interior harness (green plug by the ecu) is pinned differently. You can swap the 99-00 Si in a 96-98 EK and use the 99-00 Si engine harness and ecu but you will have some problems. I don't have experience with this swap. I'd recommend staying with the same year/ generation motor as your car for simplicity. A 99-01 B swap in a 99-01 EK is truly plug and play since the B16a2 came in a Civic" question: has anyone here used a 99-00 engine harness in their 96-98 civic swap? what did you need to do to make the tach and speedo work? i believe this has to do with the green connector at the ecu. i was looking at wiring diagrams for the engine and interior harness. i wanted to ask if there was a simple solution before i pull out the DMM to trace the blue wire and blue white wire for speedo and tach signal. if i left out any key information let me know...thanks for looking. all help greatly appreciated. i also want to mention that i cant communicate with a scan tool and the engine cooling fan does not come on. i do realize this may not have anything to do with the speedo or tach problems but i wanted to mention it just in case it did.