Question

2002 Jeep Grand Cherokee Limited 4.7L V8, what is a leak down test?

Answer 1

HI there

A leak down test is when compressed air is put into a cylinder. Then you look for 10% of the air leaking. The result will show bad valves or leaking compression rings or a faulty head gasket. It's a very accurate test for locating small issues that the compression test won't find.