i swapped a d16 out of a 1990 civic si into a 1992 civic that had a d15 now when i start the car it idles at 1500rpm and surges alot.the check engine light is on also i checked for vacuum leaks and found none so far.could it be the ecu being that i went to a bigger motor or does that matter?

 

What is the code for the check engine light? You can adjust the idle by turning the idle screw on the throttle body after you have disconnected the Idle Air Control motor. Don't forget to reconnect the IAC.

 

i looked under the kick panel on the passenger side to short the plug to get the code and i wasn't sure if it was the right one so i didn't do it. in the manual it says it should be a blue plug the only one i found was brown with a blue wire with a white stripe and a solid black wire. if you know this is the right one let me know so i can get the code thank you

 

I'm pretty sure you'll need the proper ECU for that engine.

 

i fixed it it was the exhaust manifold gasket leaking thanks for your help