My computer seems to be throwing codes 4 & 21, and is in limp mode.

Following the service manual, I tested the CKP sensor at the distributor and it passed all tests (continuity between posts within spec, no continuity w/ grd). I tested the VTEC Solenoid, and that also passed with no problems (switch side had continuity, harness side had 12v).

I'm wondering if my USDM engine is messing with my JDM ECU's brain. I've read online that JDM GSR's don't have IAB's. Would that interfere with the ECU?

I have a 94 RS model, with a 95 B18C1 head, with a chipped JDM P72 ECU.


I already had a thread about a similar issue on the same car, but started a new thread with more relation to the topic.