Necessary To Remove Rear O2's w/LT's?
05-11-2006, 06:27 PM
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Necessary To Remove Rear O2's w/LT's? I know that these either have to be simmed out, tuned out or (can they be used w/cats?) i was planning on leaving these in when i put lt's in for my cats but i hear they still may fail due to abnormal readings? what is the reason for this? is it just that common for lt's to cause these to malfunction? why do lt's do this and not stock manifolds or shorties?
Thanks!
Thanks!
05-11-2006, 08:24 PM
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The OEM narrow-band 02 sensors operate within a tiny range. Basically, all they try to do is give the PCM accurate enough data about exhaust gas oxygen content to keep as close to the ideal stoichiometric ratio as possible. The before and after-cat 02 sensors are constantly comparing readings. Because LT headers move the rear 02 sensors back so far, they send exhaust gas oxygen content readings that are different enough to set a code. All the rear 02 sim does, is to send a signal to the PCM saying, "everything's fine back here." It really has nothing to do with the rear 02 sensor harnesses not being long enough. If the rear 02 sensors, as used on a typical long-tube header set-up (waaaay back there), sent an exhaust gas oxygen content reading that the PCM would accept, it would be no great trick for companies to make rear 02 sensor harnesses long enough to plug in and use.
There are LT systems that utilize specially-sized components which allow all four 02 sensors to be connected and used without setting codes.
There are LT systems that utilize specially-sized components which allow all four 02 sensors to be connected and used without setting codes.
05-11-2006, 09:56 PM
#4
Originally Posted by bichin95redta
The OEM narrow-band 02 sensors operate within a tiny range. Basically, all they try to do is give the PCM accurate enough data about exhaust gas oxygen content to keep as close to the ideal stoichiometric ratio as possible. The before and after-cat 02 sensors are constantly comparing readings. Because LT headers move the rear 02 sensors back so far, they send exhaust gas oxygen content readings that are different enough to set a code. All the rear 02 sim does, is to send a signal to the PCM saying, "everything's fine back here." It really has nothing to do with the rear 02 sensor harnesses not being long enough. If the rear 02 sensors, as used on a typical long-tube header set-up (waaaay back there), sent an exhaust gas oxygen content reading that the PCM would accept, it would be no great trick for companies to make rear 02 sensor harnesses long enough to plug in and use.
There are LT systems that utilize specially-sized components which allow all four 02 sensors to be connected and used without setting codes.
There are LT systems that utilize specially-sized components which allow all four 02 sensors to be connected and used without setting codes.
Adding to sticky.
