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Oil pressure light on at idle sometimes

I drive a 2008 mitsubishi eclipse with 74.5k Mikes on it and when I am idling at a stop my oil pressure light will sometimes be on, but on the same day on a different drive when I’m stopped it’s not on at all, I was wondering if this could hopefully just be the oil pressure sensor going bad and I could get it replaced when I do my oil change for high mileage or if there’s something else that I should go and get it checked out a lot sooner, I appreciate any feedback on this or advice on what to do, it only started happening about 2 days ago after I took my muffler off just to be a goofball and I put it back on, I know the muffler won’t do anything with oil pressure since it’s so far back away from the cats

If you don’t hear any unusual noises from the engine when the oil pressure light comes on, 99% of the time, the oil pressure switch is faulty.

Tester

I had a similar experience with a 1971 Ford Maverick I once owned. We were on a vacation and the oil pressure light started coming on when I would stop for a traffic light. I stopped the car and checked the oil. It was at the full mark on the dipstick. I started the car and listened to the engine. I reasoned that if the oil pressure was really low, the hydraulic valve lifters would be clattering. They weren’t. For the final test, I removed the oil cap which was on the valve cover. I started the engine and looked down into the valve train. I could see that oil was being pumped up to them rocker arms. I replaced the oil cap and enjoyed the rest of the vacation trip. The problem was the sender switch. I had it replaced when I got home.

For peace of mind, you should just go ahead and change the switch. If the light doesn’t come back on you are good to go. A mechanic would check the pressure with a gage to verify. If the light flicks on again after you change the switch, it would be time to see a mechanic.

Make sure your engine oil level is between the L and H marks on the dipstick. If that’s ok then ask your shop to measure the oil pressure w/their shop gauge.

Replace the oil pressure switch. You probably have a better use for your money than paying a mechanic to measure your engines oil pressure, it is unlikely that you need a new engine at such low mileage.

Not ask 'Pay ’ a shop – Your shop ? ( how many people have a relationship that lets them claim a shop as their own .

All cars tend to lose some oil pressure over time, depending on their mileage. However, ideally the oil pressure should never go too low. The flashing low oil indicator is a clear sign that not all is well under the hood. If ignored, further (ab)use of your car could seriously harm your vehicle, and you would eventually be picking up your engine parts scattered along the highway, hoping and praying that your AAA subscription hasn’t expired!

I would install a separate oil pressure gauge in the car so you can monitor this situation and know exactly what pressures you have at all times. Oil viscosity also plays a role here…if you are using oil that is as thin as water you will have lower oil pressure in an engine that is fully broken in and or has higher mileage. Sometimes adjusting the oil viscosity a tad bit thicker can make an issue like this go away.

But if you have any doubts about the integrity of the oil system or the factory oil pressure sensor then a separate oil pressure gauge is invaluable.