JDM engine swap fuel problems


Junior Member
:angry: I have a 94 civic with a 98 JDM Type-R engine in it. I kept getting a code 23 which is a knock sensor code. I just changed the knock sensor and I'm sure everything is plugged in and correctly wired. Someone mentioned to me that in Japan they use higher octane fuel than in the USA, which I'm thinking is throwing a knock code. I am using 91 octane right now. Has anybody else had this problem with a J-spec engine? Any tips please reply. Thanks. :angry:



Senior Member
Checked your timing? :shrug:

Should just double check your wiring, you did re-pin the wire at the ecu plugs rite?


HS Troll...And Mod
I work for a whole bunch of dealerships, and that is a common code in california. I talk to a whole bunch of people with SRT-4s that have Knock Sensor issue. If 91 is all you can get, thats all you can get, and its something that cant be fixed according to chrysler.


Junior Member
I checked the pin, looks good. It was the Hasport harness. I changed the fuel filter when I did the swap a month ago. All the injectors work. I just picked up some Octane booster and am going to try 93 octane and see what happens. The booster will clean the injectors anyway.


El Capitan

Junior Member
just a small question, ima noob here, but when you swapped the jdm engine what did you do to the harness, just get an aftermarket one to fit the car?


Staff member
he probably started his own thread.

anyway, if you're hitting knock like crazy, pull some timing manually. move the distributor back a little bit... drop from 16 base to 15 base or something. see if tht helps up top.


Junior Member
Yea I'm going to have to check out the timing and see what I can do. As for the wiring I used my stock civic harness. Most of the plugs are the same. I did have to change the Injector plugs, the alternator and extend the O2 sensor plug. Then I bought the Vtec wiring harness from Hasport and pluged it into all the extra plugs I needed.