Unusual behavior in your car following an oil change can be concerning. Weird behavior means unexpected or unusual behavior that wasn’t present before the oil change occurred.
This includes sudden changes in performance, strange noises, dashboard warning lights, oil leaks, increased fuel consumption, or unexpected vibrations that can sometimes occur.
Understanding these symptoms and the reasons behind them is important to quickly address and resolve the problem.
Here’s why your car is acting weird after an oil change:
1. Wrong oil type
The use of incorrect oil type in your car can cause your car to act weird after an oil change.
Engine oils come in different viscosities and formulations, and each engine requires a specific type of oil to operate optimally.
Using the wrong oil type can lead to various problems including viscosity mismatch, incorrect oil additives, and engine stress.
Engines are designed to operate with a particular viscosity (thickness) of oil. Using oil with a viscosity that’s too thin or too thick for the engine can affect lubrication.
Thin oil might not provide adequate protection, leading to increased friction and wear on engine components. Thick oil prevents proper lubrication and flow, causing strain on the engine and reducing efficiency.
Different oils contain specific additives designed to enhance performance and protect engine parts.
Therefore using oil with incorrect additives or lacking essential components can compromise the engine’s ability to withstand extreme temperatures, prevent corrosion, and maintain cleanliness.
Also, an incorrect oil type can create excessive stress on engine components, leading to overheating, reduced fuel efficiency, and potentially causing damage over time.
The solution:
Consult with a mechanic to rectify the issue. They will drain and replace the oil with the appropriate type to prevent damage to the engine.
Always check the owner’s manual for the correct oil specifications.
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2. Incorrect oil amount
A car may act weird right after an oil change due to an incorrect oil amount, that is, low oil level or overfilling.
When the oil level is too low, critical engine components may not receive proper lubrication. This lack of lubrication can lead to increased friction, overheating, and premature wear on engine parts.
Extended operation with low oil can cause severe engine damage, leading to costly repairs or even engine failure.
On the other hand, too much oil can result in the crankshaft whipping air into the oil, causing it to foam. This aerated oil loses its lubricating properties, leading to reduced oil pressure and potential damage to engine components.
Overfilling can put excess pressure on seals and gaskets, which leads to leaks that can create a mess and further reduce the oil level over time.
The solution:
Check the oil level using the dipstick or your car’s oil level indicator. If the oil level is too low or overfilled, drain or add oil as needed to reach the proper level according to the manufacturer’s specifications.
If unsure, consult a mechanic to rectify the oil level and prevent potential engine damage.
3. Oil filter issues
Issues with the oil filter during or after an oil change can affect your car’s performance.
A faulty or incorrectly installed oil filter can obstruct or restrict the flow of oil through the engine. This barrier in oil circulation can lead to inadequate lubrication of engine components, causing increased friction, heat, and potential damage.
Also, if the oil filter is damaged or improperly sealed, contaminants like dirt, debris, or old oil residue might bypass the filter and circulate through the engine.
This contamination can compromise engine performance and lead to accelerated wear and tear.
The solution:
Seek assistance from a mechanic to conduct a proper diagnosis and fix oil filter-related problems.
They will inspect the filter and its housing for proper installation, tightness, and signs of damage. The filter might need replacement or reinstallation if it is the problem.
Draining and replacing the oil is necessary if contamination is suspected due to a faulty oil filter.
Related: Car feels sluggish after oil change (Explained)
4. Loose drain plug or filter
Loose or misaligned parts within the engine or related to the oil system can cause your car to act weird following an oil change.
This is due to loose drain plugs and misaligned gasket seals on the oil filter.
If the drain plug is not properly tightened after draining the old oil, it can result in oil leaks. This leakage can lead to a decreased oil level, causing inadequate lubrication and potential damage to the engine.
The gasket seals on the oil filter or the oil pan must be correctly aligned and in good condition. If these seals are damaged, not seated correctly, or missing, they can cause oil leaks, leading to reduced oil levels and insufficient lubrication.
The solution:
Check the oil drain plug to ensure it’s securely tightened. Inspect the gasket seals, particularly on the oil filter and oil pan, to confirm they are correctly aligned and seated.
If gasket seals are damaged, worn out, or missing, they should be replaced to prevent oil leaks.
If you are unsure about how to do this, consult a mechanic for proper diagnosis and resolution.
5. Contaminated oil
Contaminated oil is oil that has been adulterated or compromised by the presence of foreign particles, debris, or residual substances.
Using contaminated oil or inadvertently introducing contaminants during an oil change can lead to various problems affecting the car’s performance including:
- Reduced lubrication efficiency: Contaminants in the oil can hinder its ability to lubricate engine components effectively. This can result in increased friction between moving parts, leading to premature wear and decreased engine performance.
- Damage to engine parts: Abrasive particles or debris in the oil can cause damage to sensitive engine parts, such as bearings or piston rings, accelerating their deterioration over time.
- Clogging of oil passages: Contaminants can obstruct oil passages, preventing the flow of oil to critical engine components. This restriction in oil flow can cause inadequate lubrication and overheating.
The solution:
Seek assistance from a mechanic to assess and rectify the issue effectively.
If contamination is the problem, they will drain and replace the oil with fresh, clean oil of the correct specification for your car.
In severe cases of contamination, an engine flush might be necessary to remove any residual contaminants and ensure proper lubrication.
6. Air intake issues
Air intake issues can impact your car’s performance following an oil change, although the direct connection between the two may not be obvious.
However, if any components related to the air intake system were inadvertently disturbed or damaged during the oil change process, it could lead to problems with your car’s operation.
The air intake system plays an important role in supplying the engine with the proper amount of air needed for combustion. If any components like hoses, sensors, or connections related to the air intake system are affected, it can result in an imbalance in the air-to-fuel ratio.
This imbalance can cause engine misfires, poor fuel combustion, and subsequently affect your car’s performance.
Disrupted airflow due to air intake issues can also lead to irregular engine idling or even cause the engine to stall, impacting your car’s ability to run smoothly.
The solution:
While air intake issues might not directly result from an oil change, ensuring that no components related to the air intake system were inadvertently affected or damaged during the oil change process is important.
If issues arise after an oil change, checking both the oil-related components and the air intake system can help diagnose and address any underlying problems affecting your car’s performance.
Seek the expertise of a qualified mechanic to diagnose air intake issues.
The diagnosis involves checking the air intake system components, including hoses, connections, and air filters, for any visible damage, disconnections, or misalignments.
7. Mechanical issues unrelated to the oil change
Sometimes, your car might show unusual behavior after an oil change due to pre-existing or coincidental mechanical issues that are unrelated to the oil change itself.
These issues may become more noticeable after the maintenance activity, creating a misconception that the oil change caused the problem.
Unrelated mechanical problems can coincide with an oil change, giving the impression that the oil change caused the issue.
For example, an aging component might fail or show signs of wear around the same time as the oil change, leading to confusion about the cause of the problem.
Also, certain mechanical issues might not immediately show themselves until after an oil change.
For example, an underlying engine issue that was already developing might become more apparent as a result of the fresh oil and increased attention paid to the car post-maintenance.
Signs of mechanical issues unrelated to the oil change include:
- Persistent warning lights: Dashboard warning lights that persist after the oil change and don’t seem related to oil pressure or lubrication issues. These may include the check engine light or other system-specific warning lights.
- Continued symptoms: Pre-existing symptoms such as strange noises, vibrations, performance issues, or leaks that persist or worsen despite the oil change.
- Newly detected problems: Suddenly noticing issues like transmission problems, suspension abnormalities, braking issues, or electrical malfunctions that are unrelated to the oil system.
The solution:
Seek the expertise of a qualified mechanic to identify the specific problem areas and underlying issues causing the unusual behavior, focusing on systems beyond the engine oil, to pinpoint and resolve any unrelated mechanical issues.