Catalytic converter turns red after 5min of running engine, the engine doesn’t shake or show any sign of difficulty running. I have replaced the spark plugs and got a new ignition coil but did not replace ignition wires. Catalytic still turns red, could the wires be the cause of this? It is a Mini Cooper 2006 1.6 R53
Yes. It is possible. Should one or more of the ignition wires become faulty then the spark plugs wouldn’t be able to ignite all the fuel properly. The un-burnt fuel then gets burned in the catalytic converter. This will cause it to glow red and often times give off a rotten egg smell.
In most cases you would have a check engine light illuminated on the dash and a code stored in the computer. These codes can direct us in the right direction as to what the cause of the issue may be. If you have the codes post them below in the comments.