Our little dog rescue recently received the donation of a 1990 Volvo 740 DL sedan (no turbo). We have no way of knowing when the timing belt was last changed (2111,000 miles on the clock). In general the car was not well cared for but it runs well now that it has had a tune-up.

Can a mechanic accurately inspect the timing belt to determine if it should be replaced? Is this engine an "interference engine" where gastly things will occurs if the timing belt breaks? Should we just go ahead and replace it? How much should that cost?

Thanks in advance!