I have done some searching of past post to try and find a table that lets you know your A/F ratio in relation to O2 voltage output. I best I could find was conflicting answers. Seems people think differently about the correct voltage output.

Anyways, if you know what it should be, would you please post the data. Also, the same would be helpful as far as TPS readings, but that is not as important.

On a side note, what is a good range for MAP data. I just got WinALDL hooked to my car and my intial readings seem high. They are rangeing roughly between 50 to 80. However, this is on a 383 with a Q-Jet. Curious if I have some small vaccum leak?

Thanks for the info,
Bill

 

If you are using a standard switching type O2 sensor than there really isn't a certain voltage value that equals and AFR. You need a wide band O2 sensor for that...to the best of my knowledge.

Also...the vacuum created at idle is VERY subjective to the size of the cam and spark advance.

 

Just as Astro said - you need a WB O2 sensor. The stock O2 sensor just doesn't work - it was designed to detect "rich or lean" around 14.7:1 - nothing else.

In fact, that is why the newer "low emission cars" are now using a WB O2 Sensor.

 

could you please tell me more about a WB O2. What it does. why you need it over a stock one. What else do it detect?

 

Here's how I understand it.

Some LEV cars are meant to run lean (like the Honda Insight and the Toyota Prius). The further away from 14.7 the AFR gets, the more inaccurate a switching O2 sensor is. So a WB is used because a certain voltage = a certain AFR. That way the ECM can accurately run the engine at say, 16.0 AFR.

In our case, a WB is used just for monitoring the AFR. It's entirely independant of the ECM.