O2 sensor diffuser? Think this could help OBDI cars?
05-04-2005, 06:09 AM
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O2 sensor diffuser? Think this could help OBDI cars?
<center><img src="http://www.mnaudi.com/mymnaudi/images/601/Picture%20006.jpg"></center><p>It's basically a 303 stainless block machined with a fitting for an O2 sensor with a stainless nut.
What it does is take the O2 sensor out of the main exhaust stream, while still letting it suck on exhaust. For 1.8T and 2.7T's its claimed to lengthen the interval between CELs when running test pipes.
What it does is take the O2 sensor out of the main exhaust stream, while still letting it suck on exhaust. For 1.8T and 2.7T's its claimed to lengthen the interval between CELs when running test pipes.
05-04-2005, 06:22 AM
#4
It looks it would impede the flow of gas to the sensor.
The sensor would be caught in an eddy and the air around it would not reflect the true content of the exhaust. I don't know how it would help.
05-04-2005, 06:56 AM
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I would think not . . .
In OBDII cars, the secondary oxygen sensor's input is to measure the efficiency of the catalyst. A secondary sensor further removed from the exhaust stream *might* not "sniff" enough unspent fuel, which will tell the ECU that the catalyst (or test pipe) is "properly" functioning.
On OBDII 1.8 and 2.7t's, this has the advantage of not "limping" or cutting back the boost maps. It serves no benefit to our OBDI cars. Arguably, using a spacer or diffuser on our cars might render a run rich situation, killing fuel economy, power, and your catalyst.
On OBDII 1.8 and 2.7t's, this has the advantage of not "limping" or cutting back the boost maps. It serves no benefit to our OBDI cars. Arguably, using a spacer or diffuser on our cars might render a run rich situation, killing fuel economy, power, and your catalyst.
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05-04-2005, 09:06 AM
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I think that's the point.
This is a hack to bypass the OBDII ECU's emission control. You put it on the sensor that's downstream of the cat to keep it out of the exhaust. This fools the computer into thinking the exhaust isn't as bad as it is when the cat is removed for a test-pipe.
This isn't for the sensor before the cat, which controls the mixture. If you used it there, the ECU wouldn't be able to get the mixture right and the engine would run terribly. This would be so on either an OBDI or OBDII car. And an OBDI car doesn't have a post-cat sensor, so there's no use for this thing.
This isn't for the sensor before the cat, which controls the mixture. If you used it there, the ECU wouldn't be able to get the mixture right and the engine would run terribly. This would be so on either an OBDI or OBDII car. And an OBDI car doesn't have a post-cat sensor, so there's no use for this thing.
05-04-2005, 04:37 PM
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My feeling is...
First - I'll admit - engines don't give a rats a$$ about feelings.
But - O2 sensors thrive on heat - and without heat to burn off crud (in the form of hydrocarbons - in this case) - they will falsely sense an over rich condition - over leaning out your mixture - (Hey - a cure for cat-stink?) causing lots of other nasty things to occur.
I can see how you hate democrats - they give your $$$ to those who do not wish to work (who spend it at the neighborhood booze -i -torium) (supporting the local economy.)
Opposed to republicans - who give your money to their campaign contributors - who invest it offshore - supporting some OTHER neighborhood's economy.
Both extremes are worthy of yours (and mine) hate.
But - O2 sensors thrive on heat - and without heat to burn off crud (in the form of hydrocarbons - in this case) - they will falsely sense an over rich condition - over leaning out your mixture - (Hey - a cure for cat-stink?) causing lots of other nasty things to occur.
I can see how you hate democrats - they give your $$$ to those who do not wish to work (who spend it at the neighborhood booze -i -torium) (supporting the local economy.)
Opposed to republicans - who give your money to their campaign contributors - who invest it offshore - supporting some OTHER neighborhood's economy.
Both extremes are worthy of yours (and mine) hate.
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