Great...i had the under the impression that i was suppose to get better gas mileage running closed loop and letting the ecu do the thinking. but after just a day of driving...to work and back home, my car bogs like crazy and now it's throwing CEL 43!! now if i'm not mistaken, this could either be my fuel system or my O2 going out. how could it be my O2 though, cause i just changed to a new one a few months ago?!? anyone ever have this problem before? it's 4 in the morning right now and i'm at work, so i'm gonna have to wait till i get home this afternoon to check it out. but any suggestions would be a great help!!

 

CEL 43 = Fuel Supply System - defective or malfunctioning fuel supply system

Not your o2 sensor

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ekb18c &raquo;</TD></TR><TR><TD CLASS="quote">CEL 43 = Fuel Supply System - defective or malfunctioning fuel supply system

Not your o2 sensor</TD></TR></TABLE>

but i've also heard that this could be caused by a defective O2 sensor as well?? is this possible? i've searched and there are a lot of people on here that say they've tried everything from switching fuel pumps, cleaning injectors, changing fuel filters, and even changing O2s and they still have it. i hope i don't fall into that category. i'm gonna go now and take a look at what's happening with my car. thanks for the input though

 

that stinks Keep us updated..

 

good luck bro...let us know what happens..

 

Or it could be just as simple as your gas cap. I got a CEL 43 because I had a bad gas cap a few back when I was running a stock ecu.

It could be your pump.

 

Follow the troublshooting procedures outlined in the helms manual for code 43.

 

When that usually happens (going from open to closed loop and having the problems you described), it usually indicates that the A/F was pretty far from stoic. one way or the other, and now the O2 is using max correction values to compensate (going back and forth). Code 43 is usually from the O2 sensor constantly reading totally rich or lean, and then flipping the other direction. The problem is usually most noticable when the O2 goes from closed loop to open loop (or vise versa). Sounds like you need to spend some time on the fuel maps and get the tables close to your target A/F. Tuning should be done with the ECU set to open loop so there is no O2 feedback. Then when you change back to closed loop, there will be smoother transitions. Good luck.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ekb18c &raquo;</TD></TR><TR><TD CLASS="quote">CEL 43 = Fuel Supply System - defective or malfunctioning fuel supply system

Not your o2 sensor</TD></TR></TABLE>

new o2 sensor fixed my code 43

 

okay, changed spark plugs and gapped them to .03 like usual, checked out fuel pump...seemed to work fine(only a few months old), check gas cap, checked out O2 and extension adapter that i made...worked fine as well. but one thing though...if i remember correctly, you're suppose to hook up the air/fuel gauge wire to the white wire on the O2 correct? well, i did so and got no signal what so ever!! tried all the other wires and non gave a single signal!! tried touching the a/f wire to the chassis and it jumped around...meaning it works right? while doing all of this, i had no CEL, so what i did was unplug my O2 while the car was running and it threw a CEL, which should mean that the O2 is working as well. so WTF is going on with my car? as of right now, i have no CEL, but every now and then, it'll bog and backfire which is not normal. also when driving and coming to a stop my vacuum will go from -20 psi to -10 psi and the after coming to a complete stop go back to -20 psi. this never happened before...may also be fuel related??

I'm would do somemore test on the damn thing but it's gonna start snowing tonight and it's already cold as hell!! plus, today when i tried driving it hard...my clutch gave out!!...guess the damn thing can't hold the torque... anyway, the CEL maybe gone for now...but i'm positive that it will come back real soon. i'll keep you guys posted.

i'm gonna call up the shop again and see what they think...and maybe have them tune my fuel maps again.

 

Sounds like the part throttle tuning might be really off. How is the full throttle running?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by roadrunner &raquo;</TD></TR><TR><TD CLASS="quote">Sounds like the part throttle tuning might be really off. How is the full throttle running?</TD></TR></TABLE>

full throttle kicks butt...tore the **** nitz out of my clutch trying that out. it's idle and part throttle that kills me.

 

sherman just get rid of the civic man, it seems that whenever you fix one thing another pops up. I have just gave up modding my car and just waiting for the evo 8.