I installed a set of four Pulstar plugs on my Saturn VUE. After a few months of improved gas mileage my vehicle began having momentary bouts of lost power. After a week or so I thought to pull the plugs to have a look and found the first plug to no longer have a sparking point and was missing a significant amount of glass where the sparking point would have been. The Pulstar company replaced the plugs. A few weeks later I noticed that my oil was down, off the stick. I had never had to put oil in between changes. The oil had never even seemed to lower between changes. With the sudden loss of so much oil I figured could only be associated with the failed plug. The plug had deteriorated quite a bit of glass and metal into the cylinder. The folks at the Pulstar company assured me their spark plug wasn't the cause of my vehicles oil loss. I inquired how to be sure of that. The Pulstar company's representative did not suggest any diagnostic. The oil loss continues at about a quart per thousand miles.