i just put a swap in and after i drive for like 15 min the check engine light comes up but when i turn the car off then on again it doesnt come up right away till i drive like 5 min, and then when im sittin at a red light the coolant temp goes up, and it seems like im gettin bad gas mileage also, any conclusions?

 

what year civic and what engine?

 

its a 94 cx hatch with a jdm b16 i used the cx harness and wired the o2 and the vtec

 

click on this link:
https://honda-tech.com/zerothread/1901557

and come back and post the code.

 

um the code its throwing is 23 (knock sensor) its wired cause i wired it, so im guessing the sensor is bad? how important is that knock senor?

 

what ecu?

 

a jdm p30, i heard that a skunk2 p28 chipped doesnt use it,