i keep getting a cel for a code 43 fuel supply system. i have changed injectors cause the car sat for a while and i thought they might be a little dirty and that helped how the car runs a little. i also tested the regulator and that wasnt my problem. what is the usual problem when you get that code. i seem to have planty of fuel pressure also but i havent acctually put a gauge on it yet

 

O2 sensor is more than likely the culprit.

 

Yes the o2 sensor causes code 43 quite often.. do a search on code 43 and im sure 80% of the time its the o2 sensor.

 

i was getting that code, so i replaced the filter and just because i had one sitting in my shop, i threw in a gsr fuel pump, code went away, i posted on here when i was getting that code and everone told me the same thing the o2, but i thought id try the filter and pump first. hope this helps

 

The ECU has Long Term and Short Term Fuel Trim parameters in order to keep the system operating like it should. It helps to compensate for things like clogged fuel injectors, clogged fuel filters, etc.

So if the ECU sees that the O2 sensor isn't swinging like it should, it uses these parameters to get it swinging again (it has a range of +/- 20%) and if the full adjustment range is used up, you'll get this code. Hell, if the O2 signal input was shorted to ground by mistake, this code would pop up.

So is the O2 sensor, or its wiring, really the culprit? Or is some other fuel related component the culprit (like it was for a1320honda)?

If you've got over 75k miles on the O2 sensor, its served a useful life (they don't last forever anyway). Now throw on a turbo or anything else that makes the car run richer and you've shortened the O2 life a little more. Have you been burning oil or coolant - these will accelerate the death of an O2 as well.

 

the car runs great when its cold, but as the car warms up it loses power and really doesnt like to idle. as far as i can tell the wiring looks good. i also put a new fuel filter on and it seemed to help the idle very slightly. i think i have a few o2 sensors sitting around so i will try that. i was leaning toward the o2 sensor too, but figured i would ask, my next idea was the fuel pump thinking maybe as the pump runs it was getting warm and not pumping like it should. im really not in the mood to drop the tank to do that so lets hope for the o2 sensor. thanks for all the help and any more ideas are welcome.

 

i would definatly say the o2 if it runs like crap when it warms up, when its cold it has a base setting at which to idle, after it warms up it starts to pull all the info from the sensors to adjust the parameters to keep the car running, so when it warms its trying to adjust the fuel to what the o2 says, and if the o2 says its way lean or rich, itll compensate for that, so if you have a few extra o2's lying around, throw one in and see, couldnt hurt.

 

i also have this noise that comes around about the same way as the car starts to run bad too. i am wondering if it is pinging due to the o2 sensor not giving it the fuel it needs. it comes around after the car is warm and when i am between 2k and 3k rpms with light throttle. just enough to maintian speed. i also kinda sounds like a rod knock but i am really hoping against that for right now. i have swap plans but in about 6 months