I have a 2007 Renault Logan (Diesel) , it start in early morning in one self ( cold engine) but it was run more then 20 k.m. or after Engine warmed up then shut down the car and restart the car 10 min later its take 3 to 4 self to start the car..... what's the problem ? please suggest me.

it's a french car, they tend to fall apart when 11 years old. But a worn engine will do that, if it starts up eventually but smokes black when it does, engine is flat wearing out inside and flooding it out when hot.

what the solution ? and what part i will change to solve the problem ?

example: spark plug or fuel injector etc...,