Wanting to know what is the first step in trouble shooting the problem
My car has 231000 miles.
My car has an automatic transmission.
Hi there. There could be an issue with the spark plugs not firing causing excessive amounts of hydro carbons (raw fuel) to go into the exhaust system. When excessive fuel goes into the exhaust system, the catalytic converter will glow red as it burns off the fuel. This is considered a rich condition. Check the spark plugs for a spark. If there is no spark on one or two spark plugs, then I recommend replacing the spark plugs and the spark plug wires as a set with the OEM specific parts. This will ensure that the spark plugs will have a spark and operate normally. If you need further assistance with your catalytic converter glowing red, then seek out a professional, such as one from Your Mechanic, to help you.
Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing