New cat is glowing red

I’ve replaced the upper catalytic converter the manifold gasket the lower connector pipe below the cat new gaskets for all the new pipes and I’ve replaced the upstream and downstream o2 censors so far checked the spark plugs them seem to be fine no fuel or oil indicating a misfire any help would be appreciated greatly or Atleast send me in the right direction

Scan the computer data re fuel trim, up stream O2, codes, etc.

Check cam and ignition timing.
How many miles on this thing?

I’ll say it. Why did you replace the old one?

Glowing red…over rich condition, the cat is working its tail off and will melt internally if you don’t find the problem.

The check engine light must be on, right?


What year model and was it running sluggish before the reason for replacing the converter?

Some show 2 converters. The front and center. You replaced the front. A clogged center will cause the front to glow red along with frying the engine eventually. Eventually could mean very soon and a fire hazard is certainly a very possible option.


It’s a 2006 Scion tC So I replaced both and the resonator pipe I replaced both of them because it was running codes for bad catalyst flow below bank 1 and 2 figured while I was at it replace the connector pipe between both and start fresh and o2 censors as well to be safe but the cat connected to the manifold is still glowing red but the lower is not CEL is on again just waiting to get my obd2 reader back from someone but maybe spark plugs, ignition coils or MAF? I’m not sure where to start after this exhaust valves didn’t seem bad when I pulled the manifold off