Sounds like you have a cylinder not firing.
So the unburned gas is getting to the cat, and the cat is burning it off, causing it to glow red.
You’ll need to do a load balance test to see which cylinder is dead.
Have the engine idling with a low RPM tachometer hooked up.
Remove one spark plug wire,
Make note of any change in RPM.
Reinstall spark plug wire and move to the next one.
When you get to one and the RPM doesn’t change, that’s the bad one.
Now you know where look, you just have to figure out why that cylinder is not sparking.
Remember spark plug wires can have 40,000 volts in them. And the electricity can jump about 1 inch at that voltage.
Take precautions and use the proper tools to keep yourself from getting shocked.
PS, most Dwell meters at auto part stores have a low rpm range on them, and they can be bought for about $10.
Thursday, December 11th, 2008 AT 4:23 PM