Consequences of ignoring O2 sensor replace?
- Thread starter TN22Corps
- Start date
Register to hide this ad
Beyond suffering below par MPG and power... not sure. I suppose if it goes long enough and starts to run too lean it'll run your engine hotter than you want it to, or <s>if it runs too rich</s> you may earn some backfires (Edited from correction below). Neither of those are great things...
It's an easy enough part to replace if you're seeing the CEL and getting the O2 codes, and while it's not the cheapest piece to replace, it's also not that expensive considering it could cost you extra at the pump and lead to more engine wear & tear prematurely.
Just my 2 cents.
It's an easy enough part to replace if you're seeing the CEL and getting the O2 codes, and while it's not the cheapest piece to replace, it's also not that expensive considering it could cost you extra at the pump and lead to more engine wear & tear prematurely.
Just my 2 cents.
Last edited:
mikebontoft
New member
Well here's the thing... if you're talking about the post cat 02 sensor, don't worry about it til you get a check engine light.
the post cat (02S sensor 2) 02 only reads catalyst efficiency. the first 02 you want to keep running smooth. This one dictates engine air/fuel ratio based in how the engine runs. this sensor will affect your mileage. the other will not.
Lean conditions cause backfires too... just thought I'd offer a correction on that
the post cat (02S sensor 2) 02 only reads catalyst efficiency. the first 02 you want to keep running smooth. This one dictates engine air/fuel ratio based in how the engine runs. this sensor will affect your mileage. the other will not.
Lean conditions cause backfires too... just thought I'd offer a correction on that
shootmymime
New member
"Lean conditions cause backfires too... just thought I'd offer a correction on that" he is correct
the way o2 sensors work is that they read the burnt/unbernt fuel in the exhaust. that info is transmitted by way of numbers. the computer has parameters that it accepts the numbers from the O2 sensor. as an example the computer has set numbers such as 4-7, anything outside those numbers that the O2 sensor gives off will cause a code to be thrown.
the way o2 sensors work is that they read the burnt/unbernt fuel in the exhaust. that info is transmitted by way of numbers. the computer has parameters that it accepts the numbers from the O2 sensor. as an example the computer has set numbers such as 4-7, anything outside those numbers that the O2 sensor gives off will cause a code to be thrown.
mikebontoft
New member
usually the range is from .4v to 1.7v if memory serves me correct. it changes based on the carbon content (as you said, unburnt fuel). the computer oscillates the mixture between rich and lean to help keep the cat at its optimal temperature. if its gets a voltage reading from the 02 that sits too high or low on average it will throw a code.
I wanted to specify about the lean mixture because a rich burn won't cause a true backfire through the intake... that happens when you hardly have any fuel.
also I hate you because you have my dream mustang. I've been looking for that 70-73 sportsroof style lately. only difference is I love the grabber blue.
I wanted to specify about the lean mixture because a rich burn won't cause a true backfire through the intake... that happens when you hardly have any fuel.
also I hate you because you have my dream mustang. I've been looking for that 70-73 sportsroof style lately. only difference is I love the grabber blue.
I was more thinking about the burst of flames out of the tailpipe than the intake in the rich mixes... :flamethrwoer2:
mikebontoft
New member
oh I'm sure you did my little turbo Mazda liked going rich because I vented the blow off valve to air. I have a side exit exhaust on it and man that thing pops constantly. loves going pig rich at high boost and looking like a diesel but with brown smoke.
OK off topic I know, but we did answer the ops question. keep on top of that front 02! don't worry so much about the rear.
my little turbo Mazda liked going rich because I vented the blow off valve to air. I have a side exit exhaust on it and man that thing pops constantly. loves going pig rich at high boost and looking like a diesel but with brown smoke.OK off topic I know, but we did answer the ops question. keep on top of that front 02! don't worry so much about the rear.
mikebontoft
New member
96 and newer vehicles with OBDII have pre and post cat sensors at a very minimum.
One nice thing about Toyotas, is the OEM O2 sensors are Denso which are normally cheaper than other brands such as Bosch. Rather than going through a Toyota dealer, I picked up some exact fit Denso 02 sensors from Amazon for around $60 each. The wires were about 1"-2" longer than the original OE sensors but otherwise the sensor and plug were identical to what I took out. Even the gasket was an exact match.
