I dropped the exhaust and noticed a orange-colored spider-like substance on the INLET side of catlytic converter.

Any ideas of what that could be ? I could still cleary see through the cells.

Thanks,
:-) neil

1988 E36T AMG w/1995 C36 drivetrain

Can you remove any of this orange stuff?
That is typically the first sign of catalyst meltdown.
Install the exhaust, and get the exhaust gas tested with a printout.
Post the printout here for further diagnosis/answer.





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