undertheradar

I had a bad primary 02 sensor on the Y7. Just replaced it with a new one, will the ecu reset it self after a few minutes of running or will I need to manually reset it? Can I go to the parts store and use the OBD2 scanner to clear the code?

I don't want to reset the ecu unless I absolutely have to....I need to smog the car tomorrow, and if I do that I'll have to wait a week till the drive cycles are all done.

Anybody have any input?

E-brake or Handbrake

I cleared my o2 sensor code right away when I replaced mine. Otherwise, unhook the negative on the battery for 10 minutes.

undertheradar

Did it clear on its own? I just replaced it out in the parking lot here at work and ran it for a minute or so to see how it ran (it was idling very low before) and it's still doing it. I still have the CEL as well......oh well, I'll just drive to the autozone after work and clear the code with the scanner.


As far as resetting the ecu:

I don't want to do that because I need to smog my car tomorrow and the drive cycles won't be finished by then if I reset it. If the drive cycles arent finished, the car won't pass.

E-brake or Handbrake

Sorry but what is a "drive cycle"?

TheShad0w

Its about 100 miles before it will change.... trust me, did allot of experiments with this once, you better off driving untill it goes off, because there nothing like resetting the battery and thinking its fixed then 100 miles later comes on.

undertheradar

Yeah....I know. Originally the CEL came on and I didn't check the code...I just reset the ECU and went to get smogged. Passed emissions but failed the function check. Car was still running fine till about 100 miles later and the CEL came on again. The whole time the cEL was on it would idle really low and rough. Went and scanned the code and it was the primary 02 sensor. Had to wait a week or so toget the sensor, and now it's installed. I'm hoping the OBD2 scanner will clear the code without having to reset the whole ecu.


To the question about "drive cycles"....

when you reset the ECU, you wipe out the memory thats been stored. It takes a certain number of different types of driving (freeway, stop and go, etc) in order for all the sensors to report back to the ECU that everything is okay. Thats why if you just fix the CEL and not the problem, the CEL may not come on for a few days.

TheShad0w

I had the same problem, ended up replacing o2 on cat, then the cat. Light stayed off for about 5000 miles, then its came on sparaticlly. Now its back, probably the other o2, but who knows.

Turbogixxer

It takes about ~40 trips (on/off cycles) for the ECU to reset the code itself. If you have a scanner to reset the code, it will not clear the learned info that the ECU has stored.

undertheradar

So if i clear the code via the scanner, will it show up when they hook up the smog check equipment?

Turbogixxer

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by undertheradar &raquo;</TD></TR><TR><TD CLASS="quote">will it show up when they hook up the smog check equipment?</TD></TR></TABLE>

FL does not have smog, but, it will only clear the code (if done right).

E-brake or Handbrake

So what ever happened? Did the CEL shut off, did you pass emissions?