cobalt91

That glowing converter means unburnt fuel. I would check the coils.

TrAPsTaR87

Colbalt91 about a year ago I did have a thourough complete tune up done where tge coils were replaced. During the process I also had my header covers removed and cleaned is it possible that during the process the fuel injecters may have expierenced some sort of damage that took a year to come ahead to explain the unburnt gas?

cobalt91

May not be the coil its self. Check the plug and the harness goin to it. On my 91 the clips that anchor the wire harness to the front of the block broke. They were brittle with age and just broke. This caused the wires to rub against the accessory belt. The wires I had to repair the coil, crank sensor and cam sensor wires.

dicer

The code is for RPM signal. And that is those sensors, and misfire heated the cat. Fix the code like Yamae says.

The coils will not cause the computer to see a bad rpm signal, only related to cps stuff.