Bman

I'm trying to get a 3rd gen Max, but wanted to get it checked out by our local Auto Association first. Sounds pretty thorough, but they don't to a compression test on each cylinder of the engine. Instead they do what they call a "power balance test" on a scope.
What is this anyway? Sounds like a bunch of assumptions based on ignition impulses to me. What can this actually tell me about the engine's health? Is it just as reliable as a compression test, or is it worth it to take it somewhere else and get it done the old-fashioned way too? Are there any advantages to this test?

Bman

anyone?

CandiMan

iTrader: (1)

After disabling the ignition (spark) I think a power balance test is when they hook up the scope machine and measure the cranking amps while testing. The machine knows when each cylinder should be firing and measures the cranking amp during the test. If it senses a amp drop for that split second it knows that cylinder down on power. After the test it list all the cylinders and the amps it measured. It doesn't tell you why that particular cylinder down on power. A compression test is more accurate but takes time. It also gives you a actual number for each cylinder. With a little more testing during a compression test they can figure out if it's in the head or piston why it's low on power. My take, find a place that does compression test even if it means a little more money. Buying a car a big investment for some, and we have to make sure it's mechanically sound.

Bman

Thanks for replying! It just occured to me that maybe I should just do a full compression check only IF the cheapo power test shows something's wrong. I mean, it probably will take a while and won't be too cheap so that complicates things.... (I should maybe phone a place up and see how much first)