O2 sensor switching parameters?
Thread Starter
FormerVendor
Joined: Apr 2002
Posts: 278
Likes: 0
From: Yorba Linda, CA
O2 sensor switching parameters? The PCM monitors the O2's for switching from rich to lean. I know time parameter is 100 seconds, and rpm is between 1000 and 2300. I also know that if the O2's switch less than 30 times in that 100 seconds, you get P1133 or P1153. But what consitutes a "switch"......what O2 reading is rich, and what is lean?
Re: O2 sensor switching parameters? This diagram may help explain the figures you are after:
http://www.blacky.co.nz/images/efiliveO2.gif
http://www.blacky.co.nz/images/efiliveO2.gif
Thread Starter
FormerVendor
Joined: Apr 2002
Posts: 278
Likes: 0
From: Yorba Linda, CA
Re: O2 sensor switching parameters? That is very helpful. Thanks!
So what are the possible causes of insufficient switching?
I installed Hooker headers and y-pipe, then the MIL came on with codes P1133 and P1153. According to the AutoTap data (and the smell), the car was running very rich.
I ported the MAF to lean it out and I reset the PCM. It was leaner (still slightly rich by the O2 readings, but WAY too lean by the L-trims)....I still got the same codes.
I ported the MAF a little more and reset the PCM again. The O2's read WWAAYY too lean, but the L-trims improved <img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" /> The car runs incredibly well, and there is no knock retard. But the O2's are in the .780 - .830 range at WOT! So far, no codes....but at the last PCM reset it was only a matter of time before the O2's went rich and the L-trims went lean (and the codes set). Why is this happening, and what can I do to correct it?
Thanks again <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
So what are the possible causes of insufficient switching?
I installed Hooker headers and y-pipe, then the MIL came on with codes P1133 and P1153. According to the AutoTap data (and the smell), the car was running very rich.
I ported the MAF to lean it out and I reset the PCM. It was leaner (still slightly rich by the O2 readings, but WAY too lean by the L-trims)....I still got the same codes.
I ported the MAF a little more and reset the PCM again. The O2's read WWAAYY too lean, but the L-trims improved <img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" /> The car runs incredibly well, and there is no knock retard. But the O2's are in the .780 - .830 range at WOT! So far, no codes....but at the last PCM reset it was only a matter of time before the O2's went rich and the L-trims went lean (and the codes set). Why is this happening, and what can I do to correct it?
Thanks again <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
