Also check the back pressure from the cat. Remove 02/lamba sensor and install pressure gauge. I'm not sure the exact but normal back pressure is around 5-10 psi....you want to see if you have a partial clogged cat converter.

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2002 X5 4.4i Sport Wheels
2014 X5 35i M Appearance & suspension package
1995 Porsche 993
1972 Porsche 914-6
2020 GLE 450 Twin Turbo
2019 Alfa Stelvio 500hp Quadrifogilo
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