Class C 1994 with e350 chassis exhaust manifold glowing red

460 ignition system (as I mentioned earlier) tends to burn out, causing misfires, dumps unburnt fuel into the exhaust, clogs up the catalytic converter.

You won't regret replacing the parts.

I spent extensive time working on and solving 1991 460 problems. All is good now for some time. Lots more power, too ;)