98 Galant no start

Does it crank? If it cranks, try some starter fluid through the throttle bore, and see if it fires on that. If it does, that would confirm you have ignition. At that point, you have to look at fuel pressure, as well as injector pulsing.

Yes, if the cat was glowing, it probably melted the inside and is restricted. You can try locating an oxygen sensor that is before the cat(it may have dual catalysts), and remove it. See if acceleration is restored, running it with the additional exhaust flow. If it improves, the question still remains as to why the catalyst got hot. It is usually an indication of a lean fuel condition. Replacing the cat would only correct the effect, and without determining the cause of the meltdown, you may jeopardize the new one.

Just for my information, was this oxygen sensor under the vehicle on the exhaust, or closer to the engine near where the manifold connects to the pipe. The reason I ask, and some more info you might need to know, is whether or not this is a California vehicle. A California vehicle will have two cats, and the downstream oxygen sensor is actually before the cat that is under the vehicle, so it would appear to be the front sensor. An easy way to detect Federal vs. California, is look at the underhood emissions label, it will have some wording about California if it is California emissions, or it will say Federal. As far as a check for lack of air intake, a compression test might be revealing. Remove all air piping to the throttle body. It is going to have to have exhaust to have intake. Another question I have, is the check engine light on, or are any codes stored. What is the condition of the timing belt, or the timing in general? If the cam timing is off, you may have this type of condition as well.

The fuel smell may have originated from the compression test, if the injectors were firing during the test. It is going to be hard to say what you can do as far as pinpoint tests, to isolate the concern. You have a possible airflow meter concern, possibly a crank sensor, you could even have a faulty ECM. I am not sure what type of airflow sensor you have, either a vane meter, or a hot-wire sensor. If it is a hot wire, check and see that the elements aren't all caked with debris, and you can even clean them with an electrical contact cleaner. Have you plugged a scan tool in to read data? Another possibility is having some known good parts to substitute.