This month I’d like to talk about tune-ups. Years ago tune-ups were done every year, changing points, plugs and other components that wore out quickly. Then came electronic ignition that lasted a lot longer stretching the tune-ups to every few years.
Today’s high tech cars have spark plugs made with platinum tips that last even longer. Ignition wires are becoming a thing of the past. Precisely controlled computer ignition systems are very dependable. Dealers are touting no tune-ups until 100,000 miles.
Here’s where the trouble starts. Realistically even the best spark plugs wear out but rarely enough to cause a misfire or problems with the car. The normal life expectancy of spark plugs is forty to fifty thousand miles. Customers have said there is a noticeable improvement in performance with new spark plugs.
Another reason to change the spark plugs earlier is that worn plugs make the ignition system work harder causing premature failure of ignition coils and those can get pricey considering there may be one coil for each plug.
Also, if you wait until 100,000 miles to change the plugs, they’ve been in there so long they may not come out. The threads seize onto the head. If they don’t come out then you may need to replace the cylinder head. It’s better to spend money wisely now rather then have a major repair.
Fuel filters, if your car has one, should be changed at 40,000 miles. They filter more than you think. A normal fuel system pumps twice as much fuel as your engine needs. The excess fuel gets returned to the tank. So this means a 20 gallon tank will pump 40 gallons of fuel through the filter so it works a lot harder than you think. A clogged filter will cause premature wear of the fuel pump. When this happens you’ll visit us, but on the back of a tow truck.
Lastly, air filters should be checked or changed every 25,000 miles.
So next time the dealer tells you “You never need a tune-up”, have him pay for the extra labor when the spark plugs won’t come out or the fuel pump fails prematurely.