Ok my obd1 ls has been turbo for about 4000mi, it just started throwing code 43, (fuel supply), and when im crusing 60-90mph it will feel like it cuts out/ feels weird, any advice on whats going wrong? here is the fuel related setup.

s200b afr is on the lean side and uneven, need retune (related?)
rc 550cc
walbro 255

247whp
208ft lbs.

 

bump, anyone??

 

try a new 02 sensor. yours could be old and foul'd.....

how does the a/f look @ idle and @ lower engine speeds ?

 

Everytime I have gotten that code it has been due to a bad o2 sensor. I am sure it could be a few other things as well but that is the first place I would look.

 

yep definitely o2 sensor.

 

ok thanks guys, I talked to my instructors at school (all ase certified master techs) and they said pretty much the same thing, my afrs are lean at low rpm so it made my o2 sensor go bad which is making it run weird at low rpm right?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by teg racer 877 &raquo;</TD></TR><TR><TD CLASS="quote">ok thanks guys, I talked to my instructors at school (all ase certified master techs) and they said pretty much the same thing, my afrs are lean at low rpm so it made my o2 sensor go bad which is making it run weird at low rpm right?</TD></TR></TABLE>

running it lean should keep the o2 sensor clean, usually when the car is pig rich is when the o2 sensor gets contaminated.

 

disable that o2 sensor. ive never run an o2. just tune your maps accordingly and you will get just as good if not better mpg

 

but doesnt the 02 sensor help with keeping correct afr's when temp and humidity are changing? I thought the 02 sensor was important, no?

 

If I dident need to be running an o2 sensor in the first place than why did my car all of a sudden start acting funny like its super lean at low/crusing rpm (3000-4000rpm)?

I thought I had this figured out but now im more confused than when I started

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by teg racer 877 &raquo;</TD></TR><TR><TD CLASS="quote">If I dident need to be running an o2 sensor in the first place than why did my car all of a sudden start acting funny like its super lean at low/crusing rpm (3000-4000rpm)?

I thought I had this figured out but now im more confused than when I started </TD></TR></TABLE>

some people prefer to run their cars in open loop..which is fine if the weather never changes..

I run mine in closed loop/open loop like honda intended from the factory..I live in Michigan where it could be 100 degrees 100% humidity one day and 65 degrees the next day..open loop would be bad news for me.

I'd suggest just replacing the o2 sensor and then make a tuning decision after that.

 

your program should have correction factors built into it( ie iat's). that should help you stay the same a/f if the weather changes

 

yea my s200 has correction but how will the ecu read changes with no o2 sensor?

well my tuner says open loop is not a good idea so Im gonna keep the 02.

This is what im gonna do, tell me if its a good idea:

1 get new 02
2 get b&m fpr
3 get retuned a little richer (mostly at low rpm) and more even.

 

Disable o2 feedback & save your self tons of headaches.

 

B&M FPR's arent the most reliable things