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So then there will be the secondary converter ineffective and associated monitor and passing inspection, which you can with one monitor active according to the forum.
I've seen a fix to this though. If you use a long bung for the secondary oxygen sensors, this can offset them out of the exhaust stream just enough for them to detect the right concentrations.
This was in the Subaru world and was with a more primitive technology, but may still work.
I had a prodrive midpipe and their fix was this and it was very effective (the picture of this is above, for some reason the link can only go at the top of all this text).
The disclaimer here is that those people had a beefy engineering department and very likely put down formulae to determine exactly how much to recess the secondary sensor.
12 C63BS Magno Alanite Grey, 22 X3M Brooklyn Grey, 08 BMW E93, 22 Ducati Desert Sled, John Deere 3R
Secondary cat is not monitored so removing it has no effect on obdii readiness.
Originally Posted by Vladds
So then there will be the secondary converter ineffective and associated monitor and passing inspection, which you can with one monitor active according to the forum.
I've seen a fix to this though. If you use a long bung for the secondary oxygen sensors, this can offset them out of the exhaust stream just enough for them to detect the right concentrations.
This was in the Subaru world and was with a more primitive technology, but may still work.
I had a prodrive midpipe and their fix was this and it was very effective (the picture of this is above, for some reason the link can only go at the top of all this text).
The disclaimer here is that those people had a beefy engineering department and very likely put down formulae to determine exactly how much to recess the secondary sensor.
So in the C63 the rear oxygen sensors are before (upsteream) the secondary converters. I had not noticed this, although I replaced them, I didn't pay attention.
Usually, with many cars the secondary converters are also checked by the rear oxygen sensors and therefore the rear sensors are behind them.
In that case if you remove the rear converters you would then get a catalyst efficiency code.
Wow, in this car taking the rear converters out is really easy..