Excelle has been driving for 4 years, 50,000 kilometers. Now the engine of a cold car has a small "stepping" sound after driving. Is it the throttle? thank you

If it is determined that the exhaust pipe is broken, it needs to be replaced. It depends on which section is broken. It is divided into three sections: front, middle and back. From what you said, it's over. Just change the ending. The price is not good I suggest you ask at the auto parts store.

More than 50 thousand kilometers depends on the degree of carbon deposition in spark plugs. If it has not been replaced before, it is recommended to replace it.