Over the last two tanks of gas in my wife's '97 Expedition, the gas mileage has been right at 15 mpg.
The Expedition has 114k miles. We've owned it since 65k. AFAIK, it is still on the original set of spark plugs & plug wires. What kind of improvement in gas mileage, if any, can I expect once I install a new set of spark plugs & wires?
The Expedition has 114k miles. We've owned it since 65k. AFAIK, it is still on the original set of spark plugs & plug wires. What kind of improvement in gas mileage, if any, can I expect once I install a new set of spark plugs & wires?