If the cat was totally blocked, the engine may start and run briefly for a few seconds. If the cat was partially blocked the engine would run but lack serious power.
Engine mounts
No a bad muffler shouldn't, but a clogged catalytic converter will.
yes ,gud chance it is blocked
It could be your catalytic converter... yes, catalytic converters clog on these often. its fairly easy to unbolt it from the exhaust manifold. if you take it off, shine a flashlight up from the bottom, you should be able to see light from the top.
Yes, if it just started in time you will lose power and speed, replace it, it is breaking up inside.
I'd assume too much soot would build up and the truck would not start.
Catalytic converter gone bad
A clogged converter will cause an extreme loss in power, poor mileage, and hard starting. If it is clogged really, really, bad it may cause the engine to not even start.
clogged catalytic converter Agreed.......the smell of rotten eggs is an indication you have a problem with your cataltic converter
If it's coming from the rear, I would check either your catalytic converter or your muffler. Either could have pieces loose in them that would cause a rattling sound when you either push or release the throttle.
most likely your catalytic converter is clogged. if u warm it up at nite and look under the car and part of the muffler system is glowing red it is usually the catalytic converter and it will have to be replaced.
It could be a stuffed catalytic converter.