I have an EM1 with a 98+ JDM Type R Swap and will need to do emissions soon. I have header, exhaust, and no cat, but no CEL either. Have to hook up to the ECU directly to scan it rather than the OBD port. Will it pass like this? Would adding a cat (have access to one) make it pass? I've read on here that JDM ECUs will fail (I'm running the JDM ECU). I've never done emissions so I'm not sure about the process. I've heard from other people that a Civic will pass on the stock ECU without a cat, but who knows how reliable that info is. Also, what happens if you fail the emissions test? Thanks!

 

ttt

 

since your obd2 they will only scan though the OBD2 data port they will not do anything special like hook to the ecu directly. if the obd2 data port does not read its going to be an automatic fail. you are going to need to run your stock ecu or something so your data port will work.

 

^^^^Truth. And in addition, you need to run a USDM OBD2 ECU. The JDM ECU will not read through the OBD port. It doesn't have the software the scanner is looking for. If you run a stock OBD2 ECU, you'll either need to run a cat with a secondary o2, or run an o2 simulator. The JDM engine will not have a ckf sensor. That can be fixed by following this:

http://ff-squad.com/wp/?p=309