my gsr consumes oil so i'm considering doing a compression and leak down test. the compression test i can understand - using a guage attached to the spark plug hole. but the leak down... what is that? how do i test that and with what tools?

 

Well, first I'd do the compression test. I'd do it twice -- once "dry" and then once using a teaspoon of motor oil poured into each cylinder through the spark plug hole. This will help give you an indication of whether the piston rings are your problem. After you get those results, you may or may not want to continue with a leak down test. Here's a link to the procedure, but you can also find others by searching Google: http://www.carcraft.com/techar....html

 

after doing a wet and dry comp test if your numbers about the same have a buddy drive behind you on the free way and punch it and let it coast. right when it coast if blue smoke comes out your going to need new valve seals, or maybe valve guides (highly unlikely)