I have a Toyota Vitz 2002, around 190,000 km driven, The car is making a "keter keter" sound after a specific time interval, This isnt being noticed once the car is being driven its only there on idle position.
Previously the mechanic was trying to change the main fan belt pulley as it was thought the was is coming from the pulley bearing.
My mechanic questioned me if i was replacing oil on time, And recommended me to change the engine oil 2 to 3 times in a short interval because the sound could be because of the oil being old and used to much. The sound is still there i have replaced the oil around 1500 kms back only once. might change it at 2500 kms.
But since the car has done 190,000 kms. Is it safe to change the timing chain before things get worse. As i have heard if one doesn't changes the timing belt and it breaks igniting the car could damage engine valves causing irreparable or high cost repairs. So does it works the same for timing chains aswell.
Other then that the car drives fantastic, Late/long initial/morning starts are there but that i think is because of a weak fuel pump.