Checking the exhaust system (BMW 3 Series E46)

1. When the engine is cold (at least three hours after the trip) inspect the exhaust system along its entire length from the engine to the rear pipe. Ideally, the exhaust system is best inspected on a lift, but if you don't have one, then lift the car with a jack and install reliable supports under it.

2. When inspecting, look for signs of exhaust leaks, especially at connections, damage and corrosion of pipes and connections. Also inspect all brackets and hangers of the exhaust system and make sure that they are in good condition and securely hold the system in place (Fig. 11.2). Signs of exhaust leaks usually appear as black spots and are clearly visible.



3. If you sometimes hear crackling, creaking and other noises when driving the car, this may be caused by impacts and friction of the exhaust system on the bottom of the body. Try moving the exhaust system on the suspensions and see if it can touch the bottom or suspension elements.

If the system has too much range of motion, then the system's suspensions are most likely faulty. Replace them or adjust them as necessary.