Why does exhaust manifold turn red hot 2001 mercury sable?

The exhaust manifold on a 2001 Mercury Sable can turn red hot due to excessive heat generated from incomplete combustion, which often results from a rich fuel mixture, faulty spark plugs, or a malfunctioning fuel injector. Additionally, restricted exhaust flow from a clogged catalytic converter can lead to increased temperatures. Overheating can also indicate issues with the cooling system or a failing engine. It's crucial to address these problems promptly to prevent engine damage.