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How long do car ignitions last?


Car Ignition Maintenance
Newer spark plugs can often last up to 100,000 miles -- but it may not be a good idea to leave them in there quite so long.
Newer spark plugs can often last up to 100,000 miles -- but it may not be a good idea to leave them in there quite so long.
©iStockphoto.com/Karl-Friedrich Hohl

As auto part longevity has increased, the required maintenance has decreased. In fact, without moving auto parts in the ignition system, maintenance is down to nearly nothing. Even car parts like the spark plugs can make it to six figures on the odometer before being changed.

Comparing maintenance intervals for cars built in the last 10 years or so to older cars and trucks with distributors and rotors is "like comparing a washing machine to a washboard," says Macaulay. Spark plug wires, if there are any, are only changed as needed. "Manufacturers don't even list a maintenance interval," she says.

But what about all the new computerized auto parts? Don't they give out or go on the fritz? Sure, the crankshaft sensor, camshaft sensor and throttle position sensor, among others, can wear out over time, but there's no recommended interval for replacement. The powertrain control module (PCM) receives signals from these sensors all the time. If the signal stops, the check engine light comes on, and the code from the PCM will give the repair technician the necessary auto part information to find the exact sensor that needs to be replaced at that time.

This leaves almost nothing for the shade-tree mechanic to do on a Saturday afternoon. Those folks will have to be happy wrenching on cars built before 1980, with their shorter car part longevity and regular maintenance intervals. But all cars need regular oil and filter changes -- without that basic bit of maintenance, the ignition system can't continue on for 100,000-plus miles (more than 160,934 kilometers) with few repairs.

Even with this reduced maintenance, some ignition system parts will still need to be replaced. Go to the next page for more car part information.


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