Skip the auto shop - Our mechanics make house calls

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

asked by on

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.

A: Hello and thank you for your question. To c...

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.

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: The code p0102 shows up after cleaning the mass air flow sensor.

Hi and thanks for contacting Your Mechanic. The wiring harness to the mass air flow sensor (MAF) could have a break in the wires. Disconnect your battery and remove the harness to the MAF and your computer. Use a digital...

Q: Car sputtering while idling.

There could be a number of issues that can cause this concern. If the issue only occurs after the engine has warmed up. A problem in the electronic throttle control actuator either in the motor or one of the sensors...

Q: Rough idle and no power - 2004 Ford Ranger

Hi and thanks for contacting YourMechanic. Check the spark plugs and plug wires to the cylinders. Make sure that there is spark to the plugs. If there is no spark to the plugs, then check the harness to the...

Related articles

How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
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...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.