Hi I could do with some likely causes for this issue as its really annoying.

car is ex police with full service history. when you start it there is a low pitched rumbling sound from the right hand side of engine when sitting in car (the timing belt end) or chain?

it sounds to me like some belt cover or pulley is touching something at low revs as when you drive the car it is sound just when you stat it and blip the throttle.

any suggestions of what to look at would be greatly appreciated, I know there are many very gifted folks on here.

thanks

tinkerer.