97grnrs

i have an ls motor in my 91 hatch. using 90-91 ls ecu. when i hook up an air fuel gauge to my o2 it just always stays at rich, it dont move like it should so i replaced the 02 with a brand new one and does the same thing. i even ran my own wire to the pin c16 on the ecu wher 02 should be and still the same. i tried a new gauge and same thing happened. and i think somethin has to be wrong cause sometimes my CEL light will pop on when i drive and leave a code 42 for fuel supply and ppl said thats prob something with the 02 sensor so i dunno whats going on , anyone got any ideas? i tried another ecu too , same thing.

sanimalp

uh, the stock o2 sensor is a narrowband sensor. which means that it is only going to say that you are rich or lean. its not going to tell you that you are at 14.8 or 14.2 AFR because the sensor itself doesnt have that kind of resolution. for an accurate reading you need to get a wideband o2 setup, which you will have to splice the narrow band output to the ecu and wire the wideband output to the guage.

a AFR guage on a narrowband o2 is just for looks. nothing but a bunch of blinking light and meaningless information.

companies that sell widebands include Innovate, PLX, and AEM. go to the sponsor forum for the best prices.

onepoint6i

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 97grnrs &raquo;</TD></TR><TR><TD CLASS="quote">i have an ls motor in my 91 hatch. using 90-91 ls ecu. when i hook up an air fuel gauge to my o2 it just always stays at rich, it dont move like it should so i replaced the 02 with a brand new one and does the same thing. i even ran my own wire to the pin c16 on the ecu wher 02 should be and still the same. i tried a new gauge and same thing happened. and i think somethin has to be wrong cause sometimes my CEL light will pop on when i drive and leave a code 42 for fuel supply and ppl said thats prob something with the 02 sensor so i dunno whats going on , anyone got any ideas? i tried another ecu too , same thing.</TD></TR></TABLE>

sounds like you have a more serious problem with that code..you may wanna have someone check into that...

was this car converted from dpfi-mpfi?

97grnrs

sorry i meant code 43 for fuel. but the car was converted and we thought it was the wiring job so we got a complete car harness from an si and used it and ocassionally it still does the same thing. i just cant figure out why the 02 has no signal. and it dont throw a code for it.

davens

Have you considered that the gauge/o2 sensor is working properly and you're actually running rich?

It would probably be easiest to take it someplace and see what their equipment/ readings say for air-to-fuel...then you can figure out what you need to do to fix it.

dr_latino999

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by sanimalp &raquo;</TD></TR><TR><TD CLASS="quote">uh, the stock o2 sensor is a narrowband sensor. which means that it is only going to say that you are rich or lean. its not going to tell you that you are at 14.8 or 14.2 AFR because the sensor itself doesnt have that kind of resolution. for an accurate reading you need to get a wideband o2 setup, which you will have to splice the narrow band output to the ecu and wire the wideband output to the guage.

a AFR guage on a narrowband o2 is just for looks. nothing but a bunch of blinking light and meaningless information.

companies that sell widebands include Innovate, PLX, and AEM. go to the sponsor forum for the best prices. </TD></TR></TABLE> Has anyone taken this gentlemen's advice?

97grnrs

well im dumb.. all this time it must have been the stock plug for the o2. i cut it off and wired both ends together and its working fine now. reads like it should.. ha almost feels a lil slower now... oh well .

sanimalp

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 97grnrs &raquo;</TD></TR><TR><TD CLASS="quote">well im dumb.. all this time it must have been the stock plug for the o2. i cut it off and wired both ends together and its working fine now. reads like it should.. ha almost feels a lil slower now... oh well .</TD></TR></TABLE>

wait.. what did you do?

97grnrs

cut the stock o2 connector plug off and hardwired it. works well. till i used sea foam and it killed the o2 again, but i just switched it again and its working great now.

sanimalp

how did you hard wire it.. with solder??