My check engine light came on while I was driving around. This is the second time this happened so I pulled the code this time. The light only comes on every once in awhile and only after 5-10 minutes of driving. Code 43 is, "fuel supply system defective or malfunctioning fuel supply system". If I turn off the car and start it again it goes away. I did a search and from what I read it could be the oxygen sensor. I haven't changed the o2 sensor, the car has 122,000 miles on the car so maybe thats it.

Here's my setup: 440cc injectors (saturated), hondata s100 w/boost (tuned), stock intank fuel pump.

 

bump for the night crew

 

The stock ECU can add substract 20% fuel for closed loop.......if you are running too rich or lean during closed loop, and the ecu sees rich/lean after 20%, it will throw that code........

hope this helps.......

 

code 43
it could be so many different things, i had the problem a year ago on my crx
i changed many things before getting the problem fixed
fuel pump, fuel filter, injectors, o2 sensor, fcked ecu, basically anything fuel related could be it
good luck

 

I dont know if this is why your throwing the code, but why are you running a stock intank, maybe the puny stock one is causing you too run lean

 

maybe a bad o2 sensor

 

There's nothing wrong with a stock intank fuel pump. I have a fuel pressure gauge mounted above the fuel filter and it reads the correct pressure, 40psi. If the stock intank went bad wouldn't it read less pressure? I'm going to change the o2 sensor and hope that fixes the problem. The check engine light comes on after I've been driving around for 5-10 minutes. The car isn't running lean, it was dynoed last week and it put down 289 whp at 12 psi (stock ls motor). The afr was 12:1.