[Hester]

I bought ight that leak down tester from Harbor Freight too. I haven't used it on the 911 but I have used it. You're not taking any really precise measurements with it so I don't think spending more money is going to make much of a difference. It seems to me that the leak down test is best used for pinpointing a problem that has already presented itself as pretty obvious (i.e., a compression loss that is creating a miss/loss of power).