So, does this means the stalling is GOOD, a well sealed engine performing as it should? I'm not curious enough to continue on with "test" unless there's some significant benefit to be gained by making it right. The engine that did not stall (but still built up pressure) is in a car that has some vacuum deficiences, could this be related? The engine that stalled definitely smokes more than the other one, but it still runs very strong. It is the engine w/207K on it.