Oldsmobile Alero Spark Plug Replacement Cost

Know what price you should pay to get your vehicle fixed.

Spark Plug Replacement
The average cost for an Oldsmobile Alero spark plug replacement is between $107 and $130. Labor costs are estimated between $61 and $78 while parts are priced between $46 and $52. Estimate does not include taxes and fees.
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Spark Plug Replacement

What is a spark plug?

Spark Plugs are a crucial part of the vehicle’s ignition system. They have one roll, and that is to provide the spark that ignites the air/fuel mixture inside the engine, thus creating the chain-reaction that generates the engine’s power.

How does the spark plug work?

Spark plugs are part of a small group of parts that make up the ignition system. As the name implies, the ignition system’s sole function is to ignite the air/fuel mixture as it enters the engine. To accomplish this task, the spark plug turns high voltage electricity from the ignition coil into a strong spark inside the engine.

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What are the symptoms related to a bad spark plug?

As we discussed, spark plugs are necessary for any gasoline engine to run. When they fail, the engine is in a constant state of attempting to ignite air and fuel, but cannot. The first sign will be the check engine light, which may appear solid or flashing. This can happen many times before the spark plug fails completely, or continuously until repaired. It is important to understand that the check engine light can mean many things, and scanning the vehicle with an appropriate scanning tool is necessary to identify why the check engine light is on. Upon scanning the vehicle, on-board diagnostic (OBD) trouble codes will be displayed, and the following codes can indicate spark plug failure: P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0307, P0308, P0309, P0310, P0311 and P03012. All of these codes indicate a misfire, and the driver would likely notice one or more of the following: Engine vibrations, Rough idling, Poor gas mileage, Excessive cranking time needed to start the engine, Power loss or surging. In extreme circumstances, the engine may stall, or fail to start.

Can I drive with a spark plug problem?

Driving with the presence of the mentioned symptoms sends unburned fuel from the engine into the exhaust at a higher rate, and causes undue stress on the catalytic converter, the engine's exhaust cleaner. Since the catalytic converter is not made to handle a large amount of unburned fuel, failure may occur, and necessitate costly repairs.

How often do spark plugs need to be replaced?

Spark plugs have no moving parts, but they are exposed to extremely high temperatures, fire, gasoline, carbon, and high pressure. Even with this harsh environment, failure is most common after 100,000 miles of use under normal driving conditions, but is greatly shortened if the vehicle is used under harsh conditions.

How are spark plug issues diagnosed?

A vehicle with the mentioned symptoms must first be connected to a professional scan tool, which will allow the technician to understand why the engine may not be operating correctly. If the spark plugs are suspected, they are checked for proper connection with the spark ignition coil, or spark plug wire on older models. If contact is confirmed good, the spark plugs must be removed, and the spark plug gap must be checked. If the gap is too small because of corrosion, or too large because or deterioration, they will be replaced. If the spark plug is in good condition, a spark plug tester is used to indicate whether or not the spark plug produces spark.

How is a spark plug replaced?

Replacement of spark plugs on newer vehicles requires the removal of the engine cover, ignition coil harness and ignition coils, and the finally the spark plugs. For most older vehicles only the spark plug wires and spark plugs are required. There are cases in which the spark plugs are not accessible without raising or leaning the engine. Once the spark plugs are removed, the gap on the new spark plug is set to specification, and installed into the head with an anti-seize compound and proper torque. Prior to reinstalling the spark plug wire, or ignition coil, dielectric grease is applied to the spark plug terminal to promote transfer of electricity.

RepairPal Recommendations for spark plug issues

We recommend replacement of the spark plugs in accordance with the factory specified maintenance intervals. In most cases, this scheduled allows the spark plugs to be changed before they become faulty, which saves money on diagnostic fees.

What to look out for when dealing with spark plug issues

The cost of spark plug replacement can be surprisingly low or seemingly outrageous. Spark plug replacement cost is cheaper as preventive maintenance because no diagnostics have to be performed. Other factors are vehicle make and model, repair facility selection, and the number and type of spark plugs being replaced. Since some models have hard to reach or more expensive spark plugs, the cost rises and falls for both parts and labor. Different engines use anywhere from 3 to 16 spark plugs which cause the cost for parts to further fluctuate, and repair facilities tend to have different hourly rates for performing services. The RepairPal Fair Price Estimator can provide you with a reliable estimate for your specific vehicle to be repaired or serviced at a local facility.

Can I replace the spark plug myself?

Replacing your spark plugs can be one of the easiest, or frustrating experiences you can have as a DIYer. The benefits are labor savings, but the pitfalls can be extremely costly if you are not properly prepared. The position of your spark plugs may be extremely tight, and even require the engine mounts to be removed. However, with most four cylinder engines, the job can be pleasant, easy, and quick. If you choose to DIY, ensure you have the proper spark plug gap, use anti-seize compound on the threads, use di-electric grease on the spark plug terminal, and make sure the threads go in straight before attempting to tighten to the manufacturer's' specifications.