I have a CEL 41 which is primary o2 sensor.. I tried everything I can to fix it myself.. changed and replaced o2 sensors new and used... took out my whole engine harness and double checked the work. I have a 97 civic ek with a jdm gsr obd2 using the civic engines harness.. how much you think it will cost me to fix 1 CEL??? this is driving me crazy and its killing my gas mileage at a time when gas prices are way to high

 

Have you cleared the code by disconecting the batt, did the cel come right back?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by rd91sib18c5r &raquo;</TD></TR><TR><TD CLASS="quote">Have you cleared the code by disconecting the batt, did the cel come right back?</TD></TR></TABLE>
yes I have numerous times.. sometimes I leave it off for 1 hour.. and it comes right back on when I start the car.. usually people say that the CEL takes a while for it to come back on but mines comes on right away when I start the car..

 

Have you always had a CEL 41 since the swap? Which ECU does your car have? If your ECU is expecting a four wire sensor and you only have a one wire - there's your problem. If it has a four wire sensor, then you need to troubleshoot - as you have started already.

If you're sure there was no short or open in the wiring and you have replaced the O2 sensors too, then it can only be the ECU that's the problem. You have eliminated every other possible cause for the oxygen sensor heater circuit cel. Why take it to a shop when you can go to the junkyard and get another ECU. Make sure you get the right ECU for your engine. It's easy to install.

 

Dealerships wont touch swapped cars.... If you do go to a shop it'll be best going to a performance shop, and not your typical axle/alignment/scan tool shop, etc... Have you checked the pins on your ecu make sure they are correct?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by h22civic88 &raquo;</TD></TR><TR><TD CLASS="quote">Dealerships wont touch swapped cars.... If you do go to a shop it'll be best going to a performance shop, and not your typical axle/alignment/scan tool shop, etc... Have you checked the pins on your ecu make sure they are correct?</TD></TR></TABLE>
yes I have... the only modifications I did to the stock ek engine harness was cut the IACV plugs to make it fit a 2 piece plug, add a knocksensor wire directly to ecu, changed the plugs for the IAT to a round 2 piece plug, add vtec wiring, and thats it!! I havent touched the ecu period.. its a virgin.. but maybe the o2 in it fried?? i dont know

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jadziasman &raquo;</TD></TR><TR><TD CLASS="quote">Have you always had a CEL 41 since the swap? Which ECU does your car have? If your ECU is expecting a four wire sensor and you only have a one wire - there's your problem. If it has a four wire sensor, then you need to troubleshoot - as you have started already.

If you're sure there was no short or open in the wiring and you have replaced the O2 sensors too, then it can only be the ECU that's the problem. You have eliminated every other possible cause for the oxygen sensor heater circuit cel. Why take it to a shop when you can go to the junkyard and get another ECU. Make sure you get the right ECU for your engine. It's easy to install.</TD></TR></TABLE>
Yes I always had a CEL 41... I have a JDM p72 ecu Obd2... well I know that the plug for the o2 sensor has 4 wires. 2 black and 1 white and 1 green or something. so 2 heater sensors and 2 ground or something like that..

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jadziasman &raquo;</TD></TR><TR><TD CLASS="quote">Have you always had a CEL 41 since the swap? Which ECU does your car have? If your ECU is expecting a four wire sensor and you only have a one wire - there's your problem. If it has a four wire sensor, then you need to troubleshoot - as you have started already.

If you're sure there was no short or open in the wiring and you have replaced the O2 sensors too, then it can only be the ECU that's the problem. You have eliminated every other possible cause for the oxygen sensor heater circuit cel. Why take it to a shop when you can go to the junkyard and get another ECU. Make sure you get the right ECU for your engine. It's easy to install.</TD></TR></TABLE>
I dont beleive that there are any shorts in the wires.. but I brought my car to autozone the other day to use the scanner and it says error.. it couldnt read my p codes..I also have 1 plug not plugged into anything.. its a 2 piece wire round plug and the colors are red/yellow and black/yellow.. I beleive its for the EVAP purge solenoid but since my motor is jdm it doesnt have it.. well not plugging this in effect my o2 sensor at all? or theh functioning of my ecu??

 

Have you checked the O2 sensor wiring? Not just looked at it, but actually tested to see if its in good condition?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by wonder squirrel &raquo;</TD></TR><TR><TD CLASS="quote">Have you checked the O2 sensor wiring? Not just looked at it, but actually tested to see if its in good condition?</TD></TR></TABLE>
actually I have tested the wires.. I used an o2 simulator and just plugged it into the o2 plugs.. if it flashes green then it means that its working or have power going thru it.. first I tested the primary o2 sensor and it works.. then I tested the secondary o2 sensor and it doesnt flash green.. which means it doesnt work.. if thats the case then why am I gettin a code 41 for the primary o2 sensor?? doesnt make sense to me

 

Looks to me like your P72 ECU has problems. You should be able to access your ECU via the OBDII scan port. Try another one and see what happens.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jadziasman &raquo;</TD></TR><TR><TD CLASS="quote">Looks to me like your P72 ECU has problems. You should be able to access your ECU via the OBDII scan port. Try another one and see what happens.</TD></TR></TABLE>
yeah Im thinkin about tryin another scanner tomorrow.. I hope its not the ecu.. or maybe I hope it is therefore I can jsut repalce it..

 

same problem
brand new sensor but cel 41 is still on
using a stock p28 ( try 2 already) same thing
get at me if u find out the reason