Drove car with o2 unhooked accidently

[s13pignose]

Well I drove my car without my o2 hooked up because I attempted to replace it with a new one, just for maintenance reasons. Well anyway, I put my car aside and got to fooling around with another friends car...long story short time went by and I forgot all about the o2 being unhooked. I drove home and around town for a short while tonight when I noticed a CEL, and decided to go back home. There I popped the hood to look things over, and saw the 02 wire dangling:duh:

So my question is how do I get rid of the cel, and do you think any harm was done? The car still drove and felt normal, no pinging and temp gauge stayed normal. I tried resetting the ecu when I hooked the o2 back, by holding the brakes for 10min with batt disconnected. I heard thats one method, but it didn't work. For right now I just called it quits for tonight, cause its 11:56, and I just disconnected both pos and neg on the battery overnight. I guess I'll see what happens in the morning.


Also I didn't manage to get the 02 out, but a friend suggested pb blaster so I sprayed it and am letting it sit overnight.

Thanks for any suggestions

[MURPHY]

no damage done

just clear codes or disconnect the negative terminal

unless it's a hard code for some other reason it will go away after resetting or after 2 complete cycles

try this way too
Find the computer(Behind the plastic piece by the passenger foot
* Pull it out
* Turn your key to the on position
* You will see a flathead screw looking bolt on 1 side of the computer. Turn this fully clockwise
* Wait at least 2 seconds
* Turn it back to fully counterclockwise
* This will then show the trouble code - (The check engine light will blink to show this, for instance, blink..blink..blink......blink..blink, will be 32)
* After you read the code, you can start the engine
* Turn the bolt back to the clockwise position for at least 2 seconds(While running)
* Turn it back to the counterclockwise position
* Now shut the car and then start it again, this should of removed the code.

[90KAcoupe]

the o2 sensor only controls fuel at idle thats it... when the car is off idle it is unused by the ecm....

[statik]

the o2 sensor only controls fuel at idle thats it... when the car is off idle it is unused by the ecm....

it controls fuel during idle and cruising/low load (closed loop)

[s13pignose]

Yeah thats why I give much respect to people who do tuning lol. Unlike them, I don't fully understand all the senors on the car. I was under the impression that without the 02, the car wouldn't start or run long. I mean I recalled a similar incident leaving my maf unconnected, the car was going nowhere lol..it died in no time. But I don't recall any codes.

Like I said I unplug both neg and pos, and reattempt everything tommorow. Also gonna head back over to advance auto to rent their oxgensor removal kit:x: Hopefully I can get my new denso put on and get a few more mpg

Thanks again for all who posted help

[MURPHY]

it controls fuel during idle and cruising/low load (closed loop)
it monitors the o2 level in exhaust... and 2nd is for efficiency

it only makes small corrections during closed loop

deff get a o2 socket and replace if old as hell.

[s13pignose]

Hey it is the 02, because I finally was able to get the ecu out and get to the screw. I did like the instructions above, but still have the cel. I did however watch the flashes which were 3 long and 3 short...meaning 33. I went to ka24development.com and looked up the code...which was none other than front 02...I'm gonna try driving and restarting the car a couple times?

[s13pignose]

Also when I tried resetting it I accidently went past the arrow on the counterclockwise motion and I heard a click, and it allowed the screw to keep turning counter clockwise over and over..did I break something inside the ecu. Like it will stop on clockwise now if I turn lightly but doesn't take much to go past to where it keeps turning?

Also got 37 which I found to be closed loop? Know what lol

[s13pignose]

Nevermind just got a code 55, and finished through with the resetting process, and then there wasn't a cel anymore. So then I went back to the ka24development site just to look the 55 code up even though it was cleared...and all it meant was "Normal engine management system operation is indicated – this means all is OK."


Still concerned if I broke the ecu turning it counterclock wise? You think?

[usdm180sx]

Would a disc o2 sensor cause the ecu to dump fuel and make the car run rich? If that's the case running like that for too long will kill the cat.

[s13pignose]

No sure on that. All I know is I have the 02 connected now and the old code clear

[lflkajfj12123]

just unplug your battery for the night it'll clear itself shouldn't come back on unless theres still a problem

[s13pignose]

Nah I got it clear after reattempting to resett the ecu by the screw several times. Car ran good before...now seems slightly better. Cant wait to see what happens when I actually get the new 02 on...hopefully sometime this week when I'm to not to lazy to go rent the o2 socket set again