Ox sensor cycle time
Ox sensor cycle time
(OP)
It's maybe a bit of a simple question for here but....what should the duty cycle of an Ox sensor be?
Mine cycles between 0.2 and 0.8 with a peak to peak time of about 8 sec
I had it in mind that the cycle time should be about 1 sec rather than 8
Comments welcome
Mine cycles between 0.2 and 0.8 with a peak to peak time of about 8 sec
I had it in mind that the cycle time should be about 1 sec rather than 8
Comments welcome





RE: Ox sensor cycle time
Franz
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RE: Ox sensor cycle time
Older type single wire unheated O2 sensors should cycle at least once per second with the engine at idle provided the O2 sensor is warm and the system is in closed loop. At least 3 times per second at higher RPM's provided everything in the feedback loop is working properly.
The newer type 3 and 4 wire heated O2 sensors in OBD I and OBD II closed feedback loops should react more quickly than the single wire sensors throughout their operating range.
As the O2 sensors age, or become contaminated, their reaction time generally slows down causing the emission levels to rise.
A good fresh O2 sensor all by itself can detect changes in exhaust O2 content and respond with a voltage swing within a few hundreths of a second but the entire feedback loop usually doesn't need to be that responsive. It's based on the load/unload time of the catalytic converter(s)
Chumley
RE: Ox sensor cycle time
Seems like the consensus is it's way way too slow so time to change them. What sort of lifespan is normal? These are "only" 11 years/120,000 miles old
RE: Ox sensor cycle time
RE: Ox sensor cycle time
Chumley
RE: Ox sensor cycle time
and finally.....are all sensors the same?
ie can I just buy a pair of cheap generic bosch sensors and splice the cables or do I need to bend over at the Audi dealer?
RE: Ox sensor cycle time
A better question is, "Considering my 11 year old Audi V6, what is the best value for my dollar that will function properly and "chances are" won't cause any further issues? If that is your question, (which I suspect it is) then, yes, you can use the Bosch 13913 Bosch generic O2 sensors, splice them in, and save several hundred dollars over the OEM Bosch O2 sensors purchased at the Audi dealer or other aftermarket sources. If you live in an area highly subject to corrosive environments, are subject to regular biannual emission checks, do a lousy job of crimping/sealing the splices and as a result fail your emission tests and/or cause your converters to head south, well, you've been warned. Me, I use the generic Bosch sensors all the time.
The Bosch OEM O2 sensors are pricey but pretty much dummy proof. The Bosch universal sensors, less so, but with good practice, usually work fine.
Chumley
RE: Ox sensor cycle time
Thanks for re-phrasing my question and your other posts
Dollars is wrong, I have to pay for things in pounds (or body parts at the dealer) and we have an annual emissions test. On the other hand I make my living joining cables together so that they stay joined together so splicing the 13913 to the audi loom should be no problem.
Thanks again for your help