Can you install wideband sensor downstream of Catalytic convertor

[wikdsvt]

someone said you can and it won't interfere with the readings. This doesn't sound right to me. I looked online and people are 50/50 whether it gives accurate reading or not.


Doesn't the Converter remove some of the fuel to make it more emission friendly? If so, won't that give a false reading on the wideband?


please discuss.

 

[CMYZ28]

someone said you can and it won't interfere with the readings. This doesn't sound right to me. I looked online and people are 50/50 whether it gives accurate reading or not.


Doesn't the Converter remove some of the fuel to make it more emission friendly? If so, won't that give a false reading on the wideband?


please discuss.

I've never heard of it being installed after the cats. You typically want it as close to the headers as possible and at an angle (not on the bottom) to avoid water collecting on the sensor in the exhaust.

 

[ultradriver10000]

Absolutely can not, that is why the front 02 control any fuel trims on a stock ecu.

Agreed with the angle as well, water will kill the sensor asap.

 

[mustangmike6996]

If you're monitoring A/F ratio, it has to be upstream. The only purpose of the downstream (post cat) is to ensure catalyst efficiency. Look up 3 or 5-gas analysis. 5 gasses are output from the combustion. CO, CO2, NOx, O2, Hydrocarbon. The cat reduces these. The front/upstream O2 smooths fuel mixture.

Can you install it down stream, yes. Will it be accurate, no.

 

[Beigg]

I've never heard of it being installed after the cats. You typically want it as close to the headers as possible and at an angle (not on the bottom) to avoid water collecting on the sensor in the exhaust.

What he said.

I try to put the wb no more than 3" downstream/aft the factory bank 1 & 2 sensor 1 bung.

 

[04GoaT]

If you're monitoring A/F ratio, it has to be upstream. The only purpose of the downstream (post cat) is to ensure catalyst efficiency. Look up 3 or 5-gas analysis. 5 gasses are output from the combustion. CO, CO2, NOx, O2, Hydrocarbon. The cat reduces these. The front/upstream O2 smooths fuel mixture.

Not 100% true. A standard catalyst in a gasoline engine does not convert CO2 or NOx.