I just completed my D15 to y8 vtec head swap in my 88 hatch. The swap went perfect all the wiring info I got was correct, but the car keeps setting a code 43 fuel system code. The ecu I am using came from an old integra LS, the injectors are from a 92 prelude, and I am activating vtec from the shift light off my Autometer tach. The O2 sensor is from my old DX. The car is running great, good power. If you didnt see the light, you wouldnt know there was a problem. What could it be?

 

According to my alldata check the fuel pressure, fuel pressure regulator, check the 02 sensor and also check for vacuum leaks. Code 43 is fuel "SUPPLY" system.

 

check all your grounds because when i did my mini swap i had a ground problem.

 

I still dont understand why this light keeps coming on. When I had the dx head on it ran the same with no codes, I adapted the wiring harness, distributor, head, and ecu to make it a factory Si, other than the vtec part, so why when driving NORMAL (not in vtec)is the light coming on?