I have a 95 voyager 3.0L and i recently installed new spark plugs and wires. (NGK Platinum and Autolite Pro Wires). It seems that the car is running much better, but my engine has had problems in the past unrelated to ignition but i still worry messing with it. Anyway, before i installed the spark plugs the rpm level at park was about 1000 rpm and 900 in drive. When i installed the new plugs and wires the rpm for park and drive are about 100-150 rpm lower than before. I was just wondering if its normal for a new set of plugs and wires to cause that kind of decrease in rpms. Now the car does not run rough as to me it runs better but i still worry about this engine. It does shake a little, but its always done that. (probably just worn mechanical parts as the mileage is 145000) Any info would be much appreciated. Thanks.