Skip the auto shop - Our mechanics make house calls

Q: When Should Engine Spark Plugs Be Replaced?

asked by on

When should engine spark plugs be replaced?

Regularly scheduled spark plug replacement should follow the prescribed manufacturer’s recommendations listed in your owner’s manual.

With today’s advanced ignition systems and use of exotic materials, spark plugs can live for about 100,000 miles before requiring replacement.

Other reasons to replace your spark plugs would include:

  • Repair of engine misfire issues
  • Worn plugs due to high mileage, long-term storage, or engine performance malfunctions
  • Poor fuel economy
  • Emissions test failures

This is not a comprehensive list by any means.

Spark plugs are vital to the proper operation of your engine. I have personally worked on several vehicles that had close to 250,000 miles on them before coming into the shop for repair. All of the ignition system components (spark plugs, plug wires, ignition coil, distributor cap and rotor) were original to the vehicle and they too had nearly 250,000 miles of wear on them. Needless to say, with the amount of neglect these vehicles showed, the engines were totally worn out and had to be replaced.

Replacing your spark plugs when necessary will help keep your engine running well, get the most mileage from every tank of fuel, and keep those pesky emissions at their lowest levels. Should you need any help with replacing your spark plugs, contact a professional mechanic who can service your vehicle at your convenience.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Key stuck in ignition of 2001 Mercedes-Benz ML320

Hello. Most of the time, this is caused by a bad battery in the car. If the battery is low then this will occur. I typically start by checking the battery and doing a load test. If the battery is...

Q: Should we keep the car?

Hi there. If your budget is good to pay for the maintenance on the vehicle and you intend to keep the car, then I suggest on keeping the car. If you are worried about your budget on the car, then...

Q: Carbon fouled #3 and computer shows misfire on #3

If the car is running fine then it will more than likely have an exhaust leak. If the engine is starting to run a little rough again then it may have a valve issue in that cylinder. I would usually...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...