02 Sensor Code on GSR Swapped EG

[civicgsrman]

OK, every morning when i go to drive my car for the first time that day, i start it up, let it warm up a little, and drive. The check engine comes on, as soon as I start rolling out, it usually does it when the needle is 1/4 up on the temp. I turn my car off while its rollin and turn it back on the light goes away as long as the car is hot. I checked the code and it said lean o2 sensor. I think that the o2 sensor is still good, but just takes awhile to heat up to start workin, and by the time its ready the computer doesnt see it so it runs an open loop that's why CEL comes on. Can yall give me yall opinion, do you think the o2 sensor takes a while to warm up cause its old and dirty?

[SpeedAddict]

OK, every morning when i go to drive my car for the first time that day, i start it up, let it warm up a little, and drive. The check engine comes on, as soon as I start rolling out, it usually does it when the needle is 1/4 up on the temp. I turn my car off while its rollin and turn it back on the light goes away as long as the car is hot. I checked the code and it said lean o2 sensor. I think that the o2 sensor is still good, but just takes awhile to heat up to start workin, and by the time its ready the computer doesnt see it so it runs an open loop that's why CEL comes on. Can yall give me yall opinion, do you think the o2 sensor takes a while to warm up cause its old and dirty?

Your o2 sensor is most likely good. The heater element built into it helps it reach operating tempature pretty quickly.It shouldnt have anything to do with the operating temp.
Instead, when your ECT gets to a certain temp, your ECU goes into closed loop status and starts using the o2 sensor for fuel calibration. Once you start driving and the ecu will adjust fuel trim to meet the needs of the engine. If it cant adjust the fuel to the right spec, a code will be set hence the "system lean" code
Check your fuel pressure and make sure its up to spec. Also look for any exhaust leaks before the o2 sensor. You also may have a plugged up injector.

[civicgsrman]

Your o2 sensor is most likely good. The heater element built into it helps it reach operating tempature pretty quickly.It shouldnt have anything to do with the operating temp.
Instead, when your ECT gets to a certain temp, your ECU goes into closed loop status and starts using the o2 sensor for fuel calibration. Once you start driving and the ecu will adjust fuel trim to meet the needs of the engine. If it cant adjust the fuel to the right spec, a code will be set hence the "system lean" code
Check your fuel pressure and make sure its up to spec. Also look for any exhaust leaks before the o2 sensor. You also may have a plugged up injector.
So are you saying you dont think its the o2? Cause when i hit higher rpms for the purpose to get the car hotter, the light wont come on. But when i drive it slow on a cold day it comes on. I personally think its the heater element, it might be worn or dirty, no? Can anyone help me out?

[SpeedAddict]

If the heater element was bad, There would be a different code. Something like "heater circuit failure" or "heater element open circuit".
It seems to me like you are having a part throttle lean condition. Getting on it hard,your car goes into open loop status and ignores the o2 sensors feedback. Once you drive normal again,the ecu uses the o2 sensors input again. Since its seeing high voltage or too much oxygen that should be there at that particular engine RPM and Load, it is throwing a "lean condition" code...
This is what it sounds like to me. How many miles are on the engine? Particularly the injectors.
You may have low fuel pressure or a partially plugged injector(s) causing a lean condition.
Try this. Get a small hose clamp and put it around the fuel return line coming off the FPR. Just tighten it a little causing a SLIGHT restriction in the return line and increasing your fuel pressure. If the code doesnt come back after you cleared it, you know for sure its something with the fuel delivery system. But even if it does come back, you may still have a problem with the fuel delivery system....

Good luck:)