Catalytic converter reading saying 1400°F. What!?

What are said YouTubers credentials?

Your Cat is bad because the code says so, not because the temp means anything. You're focusing on what doesn't matter [temp] and getting info from unnamed people who will misdirect you because they have no credentials.

You live in FL and do not have to get another Cat just because of this.

 

I think exhaust temps can get up in that range actually. The thing to note here is is their flow through the converter in the pipe when the engine's running A lot of catalytic converters at temperatures that are extreme or at the outside of very extreme tend to melt the internals of the catalytic converter limit its flow and then it turns red hot because there's no tailpipe exhaust practically it's almost none and the little that's coming out is slowing it down so much The cat glows red soon as you get rid of the flow problem the temperature can still be up there but it's flowing so the converter or the pipe is not glowing red this is when people used to take a screwdriver and poke holes in the catalytic converter turn the car back on Flo would be happening The red would be gone and they would drive home then the next day get the converter cut out and/or replaced or piped.

 

There are no temperature sensors in the catalytic converters. The Gen 2 PIDs called "cat temp B1S1" and "cat temp B1S2" are not super well explained in the repair manual (that I've found, anyway). For Gen 3, there are docs for misfire diagnosis that explain the ECM estimates the catalyst temperature based on the flow through it and the amount of unburned fuel. Gen 2 may be doing something similar, but I haven't found the details.

I'm not sure what youtube vid you saw about the laser thermometer on the cat. If it's the same one I saw once, somebody showed using an IR temp gun with a laser guide spot, and was clearly just putting the laser spot down through a narrow gap between heat shields and thought he was measuring cat temperature that way.

The only thing that video was showing was that somebody had apparently never opened the manual for his IR temp gun, or wondered what the distance:spotsize chart on the side of his gun was for. Spoiler: you can't do it that way.

 

Most temp guns I know of unless you spend money stop it like 700 maybe a thousand degrees and then you go up in price point where most people don't want to go I think

 

Some cars use O2 sensor heater current to estimate cat temperature - more heat increases the O2 heater resistance = less current. Others just use RPM/load algorithms.

I have never found temperature to be a reliable indicator of cat function.

And it really doesn't matter. All I care about is whether the ECM is happy. That is determined by what the A/F and O2 sensors report.

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