my hyundai i20 2012 model is making a banging sound when im driving is either underneath the sparewheel carrier or the seats a banging sound like hitting an empty steel drum while driving sometimes sound occurs when i stopped and i stepped on the brakes or pulled the handbrake just after stopping. I have change suspension bushings and shocks. Pls help
A common problem with the i20 is a knocking noise at the rear which also disappears with increased speed. Many forums with no answer. I can help many owners. I replaced shocks at about 150,000 km with Monroes as I had a slight knock from rear. Knock got worse. No noise if shock taken out and replaced. After a few kms noise returned. Hyundai could not resolve. After 17 months I was desperate. Replaced with new Monroes. Still the same. Wide awake Speedys guy reported similar problem with other vehicles. Replaced with KYB shocks (genuine product too expensive). Noise gone. Like new car. Bottom bracket on shock on axle on other shocks had SIDE PLAY and were knocking against side of bolt. KYB's have sleeve inside bolt mounting which prevents horizontal play.
What you are describing could be any number of things. It sounds like something may be banging against the body or frame, which transfers audible sound to the interior of the car. It could be anything...bad motor mount, loose exhaust pipe, rough running engine, transmission mount, etc.
You will need safely jack the car up, or put it on a lift, to inspect the components under the car. It could be as simple as a heat shield touching an exhaust pipe after being bent from road debris.
Don't rule out motor mounts by sound alone. A weak motor mount can allow the engine, when revved, to twist enough that something touches causing noise.