Stupid question. posted by white22sky on June 21, 2011 at 02:50 PM
Message
is test 2-3 cylinders (say 1, 2 and 3) then go back and try again with the oil on one of them. If it changes try another cylinder to verify same or not? I also do at least 2 tests per cylinder (5 cranks or so each) on the first go-around and average the readings. Tells you pretty fast if things are mostly consistent with the test you are running....
And as others have mentioned - battery must be fully charged. That allows the engine to turn a well as possible. All spark plugs out too....