Spark plugs are present in all cars to provide the spark or electricity for ignition of the air-fuel mixture so you can start the engine. However, many people complain that when they change this component, their cars won’t start and perform poorly.
Why Won’t my Car Start After Changing the Spark Plugs? Your car won’t start after changing the spark plug because of incorrect wiring, faulty installation, damaged torque spirals. The issue comes from loosening or overtightening of spark plugs, inappropriate adjustment due to build-up of carbon, and incorrect connection of coils. In addition, the faulty crankshaft position sensor, defective spark plugs, weak batteries, and the excessive gap between plugs cause issues, and you cannot start the car.
After installing the new spark plugs, you also have to check the programming software. In addition, it is also better to reset the onboard computer system so it can recognize or add a new component.
- 1 Incorrect order of wiring
- 2 Faulty installation of spark plugs
- 3 Damaged torque spirals
- 4 Inappropriate cleaning of carbon build-up
- 5 Loose or overtightening spark plugs
- 6 Problem with reconnection of coils
- 7 Broken firing pins and ceramic coating
- 8 Issues with the fuse
- 9 Faulty Crankshaft position sensor
- 10 Weak batteries of car
- 11 Defective spark plugs
- 12 The gap in the spark plugs
Incorrect order of wiring
These plugs have several wires in which electric current flows that provide current for the ignition of cylinders.
The engine system contains four cylinders, each containing a separate wire for proper ignition and starting of the vehicle.
The order of these cables is also essential for supplying electric current and running of the engine. You can not start your vehicle if you placed the wires in the incorrect order.
The order gets disturbed when you place to remove all the wires subsequently from the four cylinders of the engine system.
In addition, the inexperienced mechanics also cause this problem. Therefore, you must take your faulty vehicles to experienced mechanics for proper servicing and resolving the issue.
Avoid removing all the wires when you are replacing them. Instead, connect each wire in subsequent order with its respective cylinder.
Faulty installation of spark plugs
It is essential to use all the ignition system cylinders for starting the car. Your vehicle won’t start when one of the cylinders does not fire appropriately.
Many people complain that they face the same issue after changing this part. The problem most commonly comes due to the wrong installation.
The wrong placement cannot able to fire all of the cylinders, and the engine cannot start. In addition, the wrong adjustment can cause an issue interruption in the firing and starting of the engine.
You must take your automobiles to the experienced mechanics for their appropriate adjustment. Then, you have to diagnose the exact problem to resolve the issue.
Damaged torque spirals
The torque spirals are the part of the spark plug that is spring-like in shape. Spirals get damaged when you hardly take the old ones for replacement purposes.
You must remove the old ones in case of any damage or fault. Sometimes you have to pull them hard when it gets jammed into the cylinder.
This part stuck into the cylinders due to overheating issue in the engine compartment. Removing the jammed part is difficult because you have to pull them harder.
In addition, you can also break the torque spirals during this process. Moreover, the new one cannot adjust because of damaged torque spirals.
The inappropriate adjustment of the new one cause issue in the firing of the engine, and you cannot start your vehicle.
The issue can also make the drivers annoyed during road trips, and it can also ruin your trip. You must carefully remove the old plugs to protect the spirals and adjust a new one.
Inappropriate cleaning of carbon build-up
The dirty air filter causes carbon build-up on the plugs, which can cause a problem in the ignition of cylinders.
Dirty filters catch more dust and dirt and cause carbon residues to accumulate there. So the carbon accumulation comes due to the presence of dust, dirt, and grim.
You have to completely clean the plugs and inputs before installing the new ones. Sometimes people complain that the issue comes after installing a new part.
The problem is due to the predeposition of carbon residues, dirt, and grime. As a result, the carbon builds up, and the presence of oil and grime causes disturbance in the ignition process.
You can fix the issue by appropriately cleaning the inputs before installation. After installing new spark plugs, you can face the issue because you do not remove these carbon residues.
You can use alcohol and vinegar solution for cleaning purposes.
Loose or overtightening spark plugs
Changing the spark plugs and not adjusting them can cause an issue because people forget to tighten them accurately.
The loose plugs are unable to provide an electrical supply for ignition. Most of the time, the issue also comes due to overtightening this part.
The overtightening and loosening problem comes when you take your car to inexperienced mechanics.
You can also face the problem when you take your vehicles to unrecognized service centers or dealerships.
Moreover, distracted drivers can also see the overtightening or loosening of the spark plug. You can fix the issue by yourself without any extra effort.
You have to take the torque wrench to tighten these correctly.
Problem with reconnection of coils
The coils are in this part, and you have to connect them appropriately after changing the spark plug.
Your engine cannot start when these coils are not connected appropriately. The faulty connections of these coils disturb the route of the ignition system.
The current travels through these coils to provide the spark and turn on the ignition. Therefore, you must attach each connector with its respective coils for the correct current flow.
The ignition route is incomplete due to the wrong connection of coils with connectors. Moreover, the short circuits also come due to this problem.
You can fix it by attaching the connectors with their respective coils with the help of an experienced mechanic. However, you should not try it at home if you do not know about it.
Broken firing pins and ceramic coating
The firing pins or ceramic coating is the same thing that is present on the spark plug and serves as a dielectric barrier.
It provides mechanical support to the electrodes and protects them from damage. The primary purpose of ceramic coating is to generate a high voltage electric current.
This high voltage electric current is specifically used to ignite the air-fuel mixture. This device’s forceful or harsh handling during installation can damage this ceramic coating.
Moreover, when you adjust it harshly, it can also cause the breakage of these firing pins. You can fix this issue by appropriately adjusting this part.
In addition, you can also handle it correctly so it cannot damage its ceramic coating.
Issues with the fuse
The fuse gets damaged, and people think there is an issue with their spark plug and change them. Sometimes you cannot start your car due to a blown fuse.
After pressing the start button, you have to check the fuse when you cannot start the engine.
The fuse blows out due to incorrect wiring and flow of current. Moreover, the surge in the power supply can also cause them to blow out.
You can check the fuse in the power distribution center and under the hood. Remove the blown-out or old fuse and replace it with a new one.
Faulty Crankshaft position sensor
The crankshaft position sensor is the component of the crankshaft that monitors the speed of RMPs and the crankshaft sensor.
In addition, it also plays an essential role in detecting the ignition timing for appropriate burning of the air-fuel mixture.
The car won’t start due to a faulty crankshaft position sensor. As a result, it cannot maintain the ignition time and monitor the speed of the crankshaft for the ignition process.
The excessive heat in the engine compartment can cause damage to this sensor, and too high a temperature also causes their melting.
You have to check the crankshaft position sensor to resolve ignition issues.
Weak batteries of car
The weak batteries cannot provide an adequate amount of electric current to the spark plugs for their functioning.
Many people change the plugs, but their car cannot start because of weak or dead batteries that cannot provide electric current.
The batteries of vehicles become weak or dead due to over usage or when you purchase the used ones from the market.
The build-up of acid on the outer side of the electrodes of the battery can also make them dead or weak.
Moreover, the issue comes when you use heavy-volt electrical equipment in your vehicles that drain excessive current from the power source.
Defective spark plugs
The defective spark plugs cause a problem with cylinders firing.
Sometimes people purchase defective ones from the market that won’t work when you install them appropriately.
Moreover, the used ones are also defective and have faults in their internal components. Therefore, when you install the damaged or defective ones, it can also cost more money.
The use of low-quality ones is also defective and causes a problem. Therefore, you should purchase the high-quality ones from the market and take the expert’s opinion before buying them.
The gap in the spark plugs
The excessive gapping between its several plugs can cause a problem in the current flow. The current cannot flow appropriately when these plugs are present at a far distance from one another.
The extra gapping than the normal range affects the engine’s performance, and you have difficulty starting your vehicle.
In addition, it can also cause misfiring in cylinders due to insufficient or delayed power supply. Gapping plugs also increases fuel mileage and the risk of wear and tear in them.
You should adjust the gap between them after taking help from experienced mechanics and taking your car to recognized dealerships.