If you have an O2 sensor, your O2 sensor will not read exhaust gases properly which may cause the ECU to make the engine run rich. Yes. Holes close to the engine in the headers may also cause unburned fuel to ignite in the headers causing backfiring.
Exhaust gasses are escaping through a hole or rotted section of exhaust system
No, it will just make the car loud.
The cause of an exhaust indicator light in a Volkswagen Beetle is probably an oxygen sensor. There also a possibility that an exhaust pipe is plugged or there is a hole due to rust.
Its a long shot but... If you have a leak in the exhaust before the oxygen sensors, the sensors will think the engine is running lean. The computer will compensate (from incorrect input data) by increasing fuel delivery, causing the air/fuel mixture to go rich. If the engine runs super rich the exhaust will be black, and very noticable when you accelerate.
Get a nut that fits the threads on the O2 sensor, or cut the socket out of the old header and drill a hole in the new header in about the same place as the old one, weld the nut or socket over the hole and attach the O2 sensor.
Just having a hole in the muffler won't cause smoke to form. Any smoke coming from an engine is caused by either environment changes (white smoke while engine is warming up), or an engine burning oil (blue smoke). Sometimes even a bad catalytic converter can cause smoke. The hole in the muffler simply gives the smoke a way out. Trying looking for external oil leaks or checking he oil level occasionally to see if it is burning oil. You may see water vapor is there is a hole in the muffler but it wouldn't last long once the muffler warms up and the moisture is burned off. She shouldn't see actual smoke unless there is a problem with the engine.
You can drill a hole in anything as long as you have a strong enough drill bit and drill. But why would you want to drill holes in your exhaust? The exhaust piping is there to route exhaust gases away from underneath the car so they don't pool up underneath your car and seep into the cabin and cause a variety of health problems.
Radiators do not have exhaust.
One of the causes could be a hole in the exhaust
Yes! Then you would have triple exhaust.
A hole in the muffler would cause a knocking sound in your muffler. A loose exhaust pipe can also cause a knocking noise.
No, but it can kill you from carbon monoxide poisoning or at the very least put you to sleep and cause you to have a wreck. Carbon monoxide is odorless, and tasteless.