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: ABS sensor and changing break fluid

Wheel speed sensors are part of the electronics of the anti-lock system. While they're an integral part of the brake system, they are separate from the hydraulic components of the brake system. Short of possibly having to move an ABS...

Q: Is it dangerous to drive your car with spark plugs misfiring?

To answer your question, yes it is unsafe to drive you car while you are having a misfire. I have provided an article written by one of our professional technicians below. https://www.yourmechanic.com/article/is-it-safe-to-drive-with-a-misfiring-cylinder.

Q: Low power and rough running. Check engine light flashing but no codes at download.

This may be caused by a few different things such as dirty fuel injectors, low fuel pressure or a dirty or failing mass air flow sensor. As you may know, dirty fuel injectors may cause intermittent fuel supply to...

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...
P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the P0052 code means This code is seen when the Engine Control Module (ECM) tries to control the...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...