engine

Hi. Any ideas gratefully received. Both at idle and when driving the engine revs suddenly increase quite dramatically. Then after 10+ seconds gradually go back to normal? Any idea why?? Many thanks

Hello everyone, I am new to the forum, and have recently purchased a 2003 Disco 2 SE7 with 114,000 miles on it for cheap because of a slight ticking sound in the motor. I usually buy old Volvos and fix them up as a fun side project, but couldn't pass on this Disco because of the price, despite...