[phpBB Debug] PHP Notice: in file /viewtopic.php on line 988: date(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'Europe/Moscow' for 'MSD/4.0/DST' instead
[phpBB Debug] PHP Notice: in file /viewtopic.php on line 988: getdate(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'Europe/Moscow' for 'MSD/4.0/DST' instead
SolaraGuy.com • View topic - O2 sensor voltage and STFT
Page 1 of 1

O2 sensor voltage and STFT

PostPosted: Mon Nov 28, 2011 5:20 pm
by Brandoe91
I was looking at some data on a obdII scanner and something doesn't seem right. Maybe someone help me understand if the data below is normal.

My o2 sensor voltage seems low at idle. I read somewhere that said .45V is the norm.
Image

Maybe the sensors are o2 sensor are bad and is the cause of my P0171 lean code.


And are short term fuel trims suppose to be at 0 at idle. It also never moved from while revving in neutral
Image

Any help Appreciated

Re: O2 sensor voltage and STFT

PostPosted: Mon Nov 28, 2011 6:21 pm
by 1gSE
http://www.autodiagnosticsandpublishing ... esting.htm

IIRC you want your STFT as close to zero as possible

Re: O2 sensor voltage and STFT

PostPosted: Tue Nov 29, 2011 9:48 am
by Brandoe91
Thanks 1gse.Now I just have to figure out what is causing the car to run lean. I already check air intake and vacuum lines for leaks. I will do some more eliminating when I get break from school next week.

Re: O2 sensor voltage and STFT

PostPosted: Tue Nov 29, 2011 10:22 am
by 1gSE
are you sc'd? Have you recently done any work on the intake side? Last time I pulled the blower, the guy helping me put the throttle body gasket on wrong and it threw a lean code....plus the afr gauge was reading like...17+ and the car did run very well

Re: O2 sensor voltage and STFT

PostPosted: Tue Nov 29, 2011 11:06 am
by Brandoe91
Nope still haven't installed it. I did however install an injen intake and you already know the headers and catback. The clamp for the coupler on the intake was a little loose, so i tightened it and reset the code.I think have an exhaust leak because those obx gaskets were sh**ty.

Re: O2 sensor voltage and STFT

PostPosted: Tue Nov 29, 2011 11:10 am
by 1gSE
Hmm...I think if it's on the header flange that could probably cause a lean code

Re: O2 sensor voltage and STFT

PostPosted: Tue Nov 29, 2011 11:48 am
by Brandoe91
Probably, since I have a a nut missing on the front flange and one or 2 on the rear flange.