Why Oil Pressure Light Comes On And Off (Top Known Causes!)

Signs Of A Failing Oil Pressure Switch

If your oil pressure light comes on and off, that’s a clear sign that you’ve got a bad or faulty oil pressure sensor (also called an oil pressure switch).

Every component used in your car is present for a purpose; however, these components are liable to spoil.

Although with proper and regular maintenance, you’d get your car to last longer. But, notwithstanding, some of the car’s crucial components – especially neglected components such as switches and valves – would wear out or begin to fail due to age.

When you’ve got a faulty oil pressure switch, it could even cause your car not to start at all; hence, to prevent all these, once you start seeing signs that the switch is failing, you should change it immediately.

Why Oil Pressure Light Comes On And Off

Oil Pressure Light Comes On And Off

The main culprit here is the oil pressure gauge/switch. This switch communicates with a connected computer to send a “Low oil pressure” warning; apparently, the warning is what illuminates the oil pressure light on your car’s dashboard.

Basically, when this warning appears, you should quickly check your oil level, and probably refill because the must-have gone low for the warning to appear.

But, if you check, and there’s enough oil, yet the warning light is still showing, that’s when you should consider getting a new switch.

On the other hand, if the oil pressure light comes on and off continuously as you’re driving, you really should find a safe place to pull over and call your mechanic – or find a near mechanic workshop to drive in.

This is advisable because if you ignore the constant blinking of the oil pressure light, it could lead to other issues, such as your car not starting up. After all, the computer thinks there’s no oil in your engine (this happens in newer cars, mostly.)

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What Are The Signs Of A Failing Oil Pressure Switch/Gauge?

1. Oil Pressure Gauge Is At Zero Always

If your car’s oil gauge stays at the zero (0) position even after an oil change, that’s a clear sign that your oil pressure switch is faulty and needs to be changed.

The oil gauge should move slightly above the middle when you refill oil, and then gradually move down as you hit more miles. So, if it stays at a position for too long – after you’ve driven many miles – it’s obviously faulty.

2. Intermittent Warning Light

The oil pressure warning light should only come on when the oil in your engine is really low. If the light stays on after refilling oil, or after you’ve checked with the dipstick and it reads your oil level is still good, then you’ve got a bad switch/sensor.

Interestingly, the oil pressure switch is not expensive, and it can be fixed quickly by a good mechanic.

For older cars that may not have a dedicated oil pressure warning light, the check engine light covers everything that has to do with the car’s engine.

These are the two common signs that you’ve got a bad oil pressure switch. However, it is important to note that your oil pressure switch might be good, instead, it could be your oil filter that is causing the issue.

What Else Causes Oil Pressure Light To Come On and Off

A bad oil filter can trigger a lot of unusual signs, even worse, it could cause damages because it may restrict oil from flowing as supposed; thus, affecting the metallic parts that make your car move.

Often ignored, but really important, the oil filter is what ensures that your engine is getting clean oil. A good oil filter would trap sediments and debris the oil might have carried as it flows through the hoses.

These sediments, over time, can clog the oil filter, and that would reduce the amount of oil that passes through it; thus, your engine won’t be getting enough oil. And once the oil pressure switch detects low oil in the engine, it’d trigger the warning light.

Now, because the oil filter is bad, sometimes, it may push in more oil into the oil, causing the oil pressure switch to detect high oil levels in the engine, which would cause the warning light to disappear.

If this scenario continues – the oil filter allowing more oil flow into the engine sometimes or restricting oil from getting into the engine – you’d notice that the oil pressure warning light would keep coming on and going off.

In this case, the pressure switch and gauge are actually okay, but the oil filter is bad. To prevent this from happening, it is advisable to change the oil filter whenever you go for an oil change, or at least, after 2 oil changes, on the third change, endeavor to change the oil filter too.

What More?

If the oil pressure light comes on and off constantly, it’s either you’ve got a bad oil pressure switch or a clogged oil filter. So, you should check these two components and have them fixed.

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