Spark Plug Trouble in Cold Weather

A wintertime dip in temperatures can put a damper on your vehicle’s engine performance, and your spark plugs may play a role. But that role may start with your battery. There are several tricks to pinpoint the cause of a sluggish cold-weather start.

The coming cold weather can affect your vehicle's engine and spark plug performance.

The first word of advice is this: Don’t let a sluggish start tempt you to run out and buy hotter car or truck spark plugs. The operating temperature of your vehicle doesn’t change with the climate temperature. So it doesn’t matter if you’re wearing a tank top or a duffle coat – stick with the manufacturer-recommended spark plug for your vehicle.

Cold temperatures render batteries less powerful. Cool weather causes an increase in electrical resistance in most electrical circuits, including your vehicle’s ignition. So if your vehicle was slow to start (or failed to start) it may be because the battery did not provide your spark plugs enough energy to bridge the gap and make a spark. To remedy this, check the gapping. Properly gapped spark plugs require less energy to create the spark that gets your engine running.

Also check to see if your spark plugs are fouled or worn. Many drivers put off checking their spark plugs until the absolutely have to, which typically happens at the first major cold snap of the winter season. Multiple failed cold start attempts can cause your engine to be flooded with gasoline. This “wet fouling” can soak the plugs and bleed off the ignition voltage before they’re able to form a spark. Spark plugs electrodes that are simply worn over time require higher voltage.

No matter the condition of your spark plugs, your car’s engine needs a little more TLC in the wintertime than it does during warmer weather. Mechanics recommend letting your car warm up for five minutes or so before taking it on the road, particularly at freeway speeds.

If it’s time to replace your spark plugs, check the E3 Spark Plugs website to make sure you’re getting the right plug for your car, truck, motorcycle, powersports vehicle or lawn and garden equipment, and to find an authorized E3 retailer near you.


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