Q: New spark plugs not working

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I just replaced the spark plugs on my car. I removed the old ones, and installed the new ones. The first couple times that I started the car, it worked fine. I ran the car for about a minute each time. But then I tried again and the car didn't start. I removed the plugs, and it looks like they are blackened and covered with carbon. The old plugs didn't look like that; just worn. Does the ECU need to adjust to the new plugs, or did I do something incorrectly?

Check to ensure that you installed the correct spark plugs and they match the ones you took out. The new replacement plugs should be iridium type and will last up to 100000 miles. If you put in the incorrect plugs, then this may cause the problem you are having. Otherwise you could have left something loose like the mass air sensor or inlet air tube while running the engine. If the engine is running rich enough to blacken the spark plugs it would set a code for a problem. A certified mobile mechanic from YourMechanic can come to your home or office to diagnose why your car is stalling.

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