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Q: Just replaced spark plugs and wires in my car and now it sputters at an idle in park.

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Smells like it's burning rich, when I press the gas it sounds healthy, the rough idle I had before with the old plugs is gone, it seems to try and sputter, try and sputter, kind of like a Harley, but it doesn't give any check engine lights. The car is a 98 that was using a 97 distributor and spark plug wire set up. I called my dad and he told me to check the gaps, what else could it be if that's not it? How do I know the spark plugs are working properly?

My car has 220000 miles.
My car has an automatic transmission.

Hello and thank you for your question. To check the spark plugs, simply remove one spark plug at a time and place it on the ground somewhere away from the engine’s belts and away from the spark plug hole.

Start the engine and see the color of the spark. If there is a strong spark and it is blue, then the spark plug is good. Check all the plugs for the same symptoms. Then, get a spark plug tester and put it into the spark plug wire without the plug. Put it to ground with about 60 thousands (0.060 on the gauge) and see if there is a spark.

If no spark, then adjust the tool with rubber pliers and see when the spark will apply. If the spark starts to show up less than 30 thousands (0.030 on the gauge) then the coil is not producing enough power for the spark plugs and wires. I recommend having a professional, such as one from YourMechanic, check out the engine management system and determine why the engine is sputtering.

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