How Do You Know if You Need New Spark Plug Wires

March 13, 2022 Post a Comment

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A spark plug wire is a basic but critical engine component. Information technology carries the high voltage (30k to 50k volts) produced past the ignition roll to the spark plug. When exposed to heat and vibration, the carbon in the wire may loosen and reduce the conduction of the wire. If you doubtable that your spark plug wires are damaged, you may be able to spot the problem yourself. Then, if a faulty wire is then stock-still or replaced, you lot tin can solve a variety of issues, including engine misfires and radio static.^[1]

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Await for concrete harm to the wires or boots, such as cuts and scorch marks. Use a flashlight or an area with adept lighting to perform a visual inspection of the spark plug wires and the cap on top of them, chosen the kicking. These will be a line of wires coming out of the cylinder caput and attached at the other end to the distributor or ignition coils. Examine the insulation around the wires as they motion abroad from the spark plugs. ^[2]
- Scorch marks signal damage due to loftier heat from the engine compartment.
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Check for corrosion betwixt the kick and the spark plug and ringlet. Remove the boot from the top of the spark plug and look at the area where the connection was made. Brand certain at that place is no discoloration or damage. And then remove the spark plug and audit the the bottom of it for discoloration or damage.^[3]

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3
Audit the spring clips that concur the wires in the distributor cap. Follow the wires abroad from the cylinder head to the other terminate, where they adhere to the distributor. Wiggle the end of the wire, making sure that the clips are holding the peak of the spark plug solidly. When undamaged, they create the pressure that keeps the wire and the plug connected solidly.^[4]
- Damaged clips may allow the wires to slip and non hold their proper position.
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1
Identify symptoms associated with a faulty spark plug wire. Lacking spark plug wire leave tell-tale signs of their deterioration. The virtually common symptoms include:
- An erratic idle
- Engine misfire
- Radio interference
- Decreased fuel mileage
- Failed emissions tests due to elevated hydrocarbon emissions or a fault lawmaking indicating cylinder misfire
- Check engine calorie-free
2
Do a visual inspection while the engine is running. Sometimes you will be able to identify a problem just by looking over the engine. Look for electrical arcs effectually the spark plug wires. As well mind for an abnormal snapping noise, which may indicate a high-voltage electrical leak.^[5]
- Accept someone else rev the engine while yous continue to look at it. Look and listen for abnormal changes, such as arcs or fume.
3
Utilize a screwdriver to exam the insulation of the wires. Get a piece of wire that is long enough to reach from a basis source to the spark plugs on your auto. Tie i stop to the shaft of a well-insulated screwdriver. Tie the other end of the wire to the basis source Then drag the screwdriver tip downwards the length of each spark plug wire, around the curlicue, and the boots. If you see an arc from a wire to the screwdriver, you have lacking wire.^[half-dozen]
- It is important to use a well-insulated screwdriver for this test. If you don't, you run the run a risk of shocking yourself.
iv

Spray down the spark plug wires to look for arcing. Fill a spray bottle with water and spray all along the wires. You volition want to focus your spray almost the boots that attach to the spark plugs to see if any arcing occurs there. If arcing is found at the kicking near the spark plug, turn off the engine and inspect the boots further.^[7]
5
Audit the within of the kicking for carbon tracking. In one case you lot have sprayed the spark plug wires and at that place has been arching, you need to wait at the inside of the boot. Remove the boot from the plug by pulling it straight up and off. Cheque inside the kicking for carbon tracking, which is a residue that leaves blackness marks all over the within of the boot. The buildup of this carbon shows that the connection is not optimal and tin lead to misfiring.^[8]
- If carbon tracking is present, the spark plug and the wire should be replaced.
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1
Locate the spark plug's resistance rating. This is typically listed in the vehicle's factory service transmission. You can also search online for the service manual of your car if y'all don't accept it on hand.^[9]
- If you don't accept your car's service manual, or yous take afterwards-market wires, you can commonly discover this information online. Do an online search that includes the brand, model, and twelvemonth of your machine and the words "spark plug resistance rating."
two
Use an ohm meter to check the resistance of the wires. This can decide if the resistance of the wire is in compliance with the recommendations. Remove the wire from the engine by pulling the kick off the spark plug and unscrewing the wire at the other end. So place one probe on each end of the wire. Make sure they bear on the metal contacts.^[10]
- Use the meter to verify that the resistance is within the range called for in the machine'southward manual.
3
Determine if your spark plug wires are routed properly. Look at the spark plug diagram in the vehicle'due south manual to aid you with this task. Trace each of the spark plug wires from its connexion on the engine block to its corresponding spark plug. Information technology is important that each wire goes to a specific spark plug.^[eleven]
- This can be a problem if you have had your spark plugs inverse and the boots become put back on in the wrong order.
- Cross coupling can create an energy drain, causing engine trouble.
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Some engines have coil-on-plug (COP) configurations that featherbed the spark plug wires completely, although a boot is notwithstanding present.
Keep the spark plug wires make clean to reduce conduction drain.
Do not assume that crossing spark plug wires is a bad sign. Some manufacturers do this to cancel out magnetic fields.

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If you have a pacemaker or a similar device you should not examination spark plug wires yourself, as an accidental daze tin can interfere with its function. Instead, rent a mechanic to test them for you.

Things You'll Need

Flashlight
Jumper wire
Screwdriver with insulated handle
Ohm meter

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Article Summary Ten

The easiest way to test your spark plug wires is past using an ohm meter to measure resistance. Look in the possessor'southward manual to discover the advisable resistance for the wires. And then, pull the boot off of the spark plug and unscrew one of the wires at the end. Place one probe on either stop of the wire touching the metallic contacts, and expect at the ohm meter to see the resistance. Make sure it matches the resistance in the manual. For tips on how to check the spark plug wires past inspecting the engine, curlicue down!

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