Does Oil Go Bad Sitting in an Engine?

October 23, 2025

Mechanic pouring oil into a car engine with a blue funnel. | Auto Clinic Care

If you haven't been using your car a lot lately - you're not alone. Many Americans have been sheltering in place and distancing themselves from public places in the midst of our current pandemic. With the decrease in travel and staying home more often, you may find that your vehicle isn't being used, either not much or at all. 



We've gotten this question a few times recently, and wanted to share our take on it - does oil go bad sitting in an engine? We get this question from car owners who haven't used their cars in weeks and are worried if they need to have an oil change sooner than planned. Let's look at some of the effects that an idle vehicle can have on the engine oil and whether or not it goes bad while sitting unmoved. 


What can happen to your car's engine oil if you don't drive for weeks at a time? Engine oil is notoriously for breaking down quickly - that is why you have to have an oil change more frequently than any other service. It also tends to get dirty fast, considering it's circulated throughout a dirty engine. So, if you aren't using your car, does the engine sit untouched and unaffected? 


The answer is, no. If your vehicle is sitting unused, dirt and dust can still dirty the engine oil. Another thing that can happen is moisture can begin to build up, especially if your car is in a damp or cold area such as a garage. What happens is the moisture contaminates the engine oil, which causes it to be much less effective and can rush or corrode interior engine parts if circulated. 


Now, does the engine oil go bad? Not necessarily. However, the best medicine for an idle vehicle is starting it up every week and letting the engine run for a good 20 minutes. Take it for a drive around your home and try to reach up to 50 MPH if possible. When the engine oil circulates, it warms up and passes through the oil filter. This will help the oil stay effective and this also helps prevent your vehicle's battery from dying (totally different topic, but also a concern for idle vehicles). 


If your car has been sitting idle for a while, we recommend checking your engine oil with the dipstick. If it looks dirty, you should change it before driving your car. Also, change it if you're due for one. Just because you aren't driving your car, doesn't mean you don't need an oil change at your car's interval. 


If you're due for an oil change, we invite you to our shop here at Auto Clinic Care. Even if you aren't sure if you need one, we can take a look and give you our expert opinion on whether or not the engine oil should be changed. Give us a call or stop by our Rockville oil change shop today! 

Is High‑Mileage Oil Really Better for Older Cars? | Auto Clinic Care
December 19, 2025
Auto Clinic Care in Rockville, MD, explains whether high-mileage oil is really better for older cars.
Mechanic inspecting a timing belt on a car engine. | Auto Clinic Care
October 23, 2025
The timing belt or timing chain is an integral part of automobiles then and now. It turns your engine’s camshaft synchronously to ensure ...
Finger pointing at worn, cracked tire with visible tread damage. | Auto Clinic Care
October 23, 2025
Auto Clinic Care discusses whether you need to replace tires that look fine. Learn about the hidden signs of tire wear to ensure your safety on the road.
Black and white certified seal stamp with text
October 23, 2025
Auto Clinic Care explains the benefits of ASE-certified technicians. Learn how their expertise ensures quality car maintenance and repairs.
Car's brake disc and caliper in a repair shop. The disc is silver, and the caliper is dark with the car raised.
October 23, 2025
If you have ever applied your brakes and either nothing happened immediately or it took a lot more pressure to get your vehicle to slow ...
Car suspension system with red springs, brake calipers, and drive axles.
October 23, 2025
Avoid Bumps and Enhance Comfort! Auto Clinic Care explains how proper car suspension keeps your ride smooth and safe.
Mechanic working on a car brake rotor. Hands hold tools near the metal disc.
October 23, 2025
You may refer to it differently, but there will come a time when your brakes will start whining. At first it might not be ...
Underside of a car in a garage, exhaust pipes, black bumper, metal components, and tires.
October 23, 2025
The exhaust system in your vehicle is important for several reasons: It ensures that the harmful engine byproducts are corrected before ...
Red and black jumper cables connected to a car battery to jumpstart the vehicle.
October 23, 2025
Auto Clinic Care explains why car batteries struggle in cold weather. Learn about the effects of low temperatures on battery performance and how to prevent issues.
Hand removing a red battery terminal cover in a car engine bay.
October 23, 2025
The team at Auto Clinic Care shares the steps to changing your car's battery at home!