Main cats removal advice needed re sensors
Thread Starter
Newbie
Joined: Jul 2012
Posts: 4
Likes: 0
From: Northern Ireland
slk55 amg
Main cats removal advice needed re sensors
Hi all I am sure this has been talked about before but I cant find anything but I am thinking of removing the main cats on slk 55 R172 and I thought this would be the best forum to try but am not sure what will the sensors pick up and are they going to show up faults. There is a sensor just before the cat and one in the middle of the cat Has anyone done this and had they any problems. Thanks
Ray
Ray
Super Member
Joined: Jun 2015
Posts: 503
Likes: 38
From: South Africa
2004 CLK55 AMG W209
Hello Ray. I will warn you that yes it is on many forums. W204 C63 as well as W203 C55 and maybe here but hey you asked so we can help.
I had no choice but to delete mine as my Country doesn't cater for the emission stringent laws like yours probably does. So I removed all as I could not find anyone selling high cel cats or any aftermarket one to replace spare a salvage yard who at the time had none. The shop simply placed stainless steel where the cats used to be and used what people call a fouler to move the sensor away from its original position. When I say original I mean, it has been spaced away using the fouler and not relocated further down or up stream from one another. It is more like an adapter that looks tube like that mounts to the bung on the exhaust and the sensor fits into it so the reading should differ and not be the same.
I still had the engine light on afterward. I did the battery removal few times to get rid of it as the light troubled me. I drove 1000km with it and eventually it went off. It only comes back on now and then if I beat the throttle hard on some days but after I covered 1000km, the car felt stronger than it did with the cats. Please note the immediate feeling after removal was much weaker. I guess the ECU adapted to the changes after time.
The best bet if you opt for this route is to get an ECU tune done then you wont have to bother or experience the ordeal I went through and then you also would not have to bother bout fitting the fouler/adapter/cheater whatever they call it.
I had no choice but to delete mine as my Country doesn't cater for the emission stringent laws like yours probably does. So I removed all as I could not find anyone selling high cel cats or any aftermarket one to replace spare a salvage yard who at the time had none. The shop simply placed stainless steel where the cats used to be and used what people call a fouler to move the sensor away from its original position. When I say original I mean, it has been spaced away using the fouler and not relocated further down or up stream from one another. It is more like an adapter that looks tube like that mounts to the bung on the exhaust and the sensor fits into it so the reading should differ and not be the same.
I still had the engine light on afterward. I did the battery removal few times to get rid of it as the light troubled me. I drove 1000km with it and eventually it went off. It only comes back on now and then if I beat the throttle hard on some days but after I covered 1000km, the car felt stronger than it did with the cats. Please note the immediate feeling after removal was much weaker. I guess the ECU adapted to the changes after time.
The best bet if you opt for this route is to get an ECU tune done then you wont have to bother or experience the ordeal I went through and then you also would not have to bother bout fitting the fouler/adapter/cheater whatever they call it.
Last edited by Khan 55; May 18, 2017 at 02:37 AM.
Member
Joined: Sep 2013
Posts: 171
Likes: 17
From: Finland
'14 E500 Coupe
Or you can find someone with Xentry/Star laptop and have him turn off the diagnostic of rear lambdas. There is a simple dragbox for this. I just did this with my SLK and couple years ago with my CLK. No need for expencive tune or never working spacer bungs.
