Lambda / Oxygen Sensors, educate me!
Discussion
The mythical world of Lambda Sensors.... I am but a Hobbit in this world and need a PH education!
Basically, I have a fine automobile upon which the Lambda sensor has died (or so says diagnostics anyway). Its a four wire lambda (2 white, a blue and a black). Am i right in thinking this is a 'wideband' lambda sensor, generally regarded as offering superior engine management over 'narrowband'? I am pretty sure I understand what it does, how and why (uses a hot wire or something to measure stoichiometric ratio and reports to ECU to alter fuel map accordingly).... but a PH explanation would be appreciated.
The next question is why are there so many different lambda probes?!! Surely they are all doing the same job and returning broadly the same values, no? If they are measuring the stoichiometric ratio surely there is only one way of measuring it?
Seeing as I need to replace the lambda probe (which has a main dealer price equivalent to the GDP of a small country), what stops me from using any 4 wire lambda probe as a replacement... or one of the 'universal' types off ebay or similar? Is the world of Lambda probes a lot more complicated than it looks?
Basically, I have a fine automobile upon which the Lambda sensor has died (or so says diagnostics anyway). Its a four wire lambda (2 white, a blue and a black). Am i right in thinking this is a 'wideband' lambda sensor, generally regarded as offering superior engine management over 'narrowband'? I am pretty sure I understand what it does, how and why (uses a hot wire or something to measure stoichiometric ratio and reports to ECU to alter fuel map accordingly).... but a PH explanation would be appreciated.
The next question is why are there so many different lambda probes?!! Surely they are all doing the same job and returning broadly the same values, no? If they are measuring the stoichiometric ratio surely there is only one way of measuring it?
Seeing as I need to replace the lambda probe (which has a main dealer price equivalent to the GDP of a small country), what stops me from using any 4 wire lambda probe as a replacement... or one of the 'universal' types off ebay or similar? Is the world of Lambda probes a lot more complicated than it looks?
Ok, well I have learnt something already! 4 wire = narrowband - thats a good start! So all 4 wire narrowband sensors are pretty much the same? Why such huge differences in price?
So I should be able to pick up a generic 4 wire sensor, splice that onto the existing loom connector and be good to go?
So I should be able to pick up a generic 4 wire sensor, splice that onto the existing loom connector and be good to go?
Scuffers said:
not all narrow band 4 wire sensores are the same...
yes they do the same job, but they vary quite a lot in terms of heater impedance, temp profiles, etc.
Interesting... tell me more. How do they vary and how does one measure the variance? How do the so-called 'universal' ones get around this?yes they do the same job, but they vary quite a lot in terms of heater impedance, temp profiles, etc.
What effects would the un-matched lambda sensor have on a car?
This is good stuff! I am learning fast here... just as a PH education should be. I see, so they are not all the same....
I checked JustLambda - they don't do one for my conveyance.
So these clever Lambda johnies are more specific than they look - where can I do some research on these? I want to understand these better.
In the interim I have heeded the sage advice and plumped for an O.E. replacement - a gentleman cannot go without leather and wood for too long...
I checked JustLambda - they don't do one for my conveyance.
So these clever Lambda johnies are more specific than they look - where can I do some research on these? I want to understand these better.
In the interim I have heeded the sage advice and plumped for an O.E. replacement - a gentleman cannot go without leather and wood for too long...
Gassing Station | General Gassing | Top of Page | What's New | My Stuff