By installing a new mufler you have changed how the car runs.
If the wrong muffler was installed it could mess up the computer until it would not run any more
orThere is a problem with the new muffler or how it is installled.your car should not stall after installing a subwoofer. your problem might be the fact that your amp and your subwoofer(s) could be using too much of your cars electricity.
It may because of a bad/clogged air filter or muffler.
if you have a cracked distributor cap then water would get inside it and make your car stall.
because if you stop immediately then the car will stall.
yes a bad converter will make car stall
Because of condensation the inside of your muffler, the muffler will begin to deteriorate (rust) over time from the inside. This can and will cause holes in the muffler. Along with the hole (s) the internal structure of the muffler will eventually break apart and plug the muffler, preventing the exhaust gas and the pressure from the engine from exiting the vehicle. This will cause what is called "back pressure" on the engine, causing it to lose power. Extreme example would be "you push the gas pedal to the floor but the car will not go more the 25 miles per hour". I would recommend you have you muffler replace. That should solve your problem.
The muffler makes your car run quiet
out of fuel?
A free flow muffler can improve mileage but by not by much. It would take a long time to recoup the cost of a new muffler.
AC runs on the battery. If the car is off and you run the AC, then start the car, it will stall.
Hole in the muffler.
idiot behind wheel