2007 Monte Carlo Low Oil Pressure

Hi Everyone! This is my first post on here and I have a pretty dumb question. So for the past two years my Monte Carlo has been saying Oil Pressure Low Stop Engine. It flicks on and off constantly and is random. My car is driving just fine. Doesnt make noise, no smell, no physical signs (From what I can tell) of damage, no overheating. I get oil changes regularly and just got another one a few weeks ago. Im about to go on a pretty long trip and was wondering what the chances are that my engine will seize in a freak deal? As said its been driving fine with no problems what so ever for the past two years with that warning light on. Engine oil shows that its good on the dipstick. Should I be fine to make the trip?

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Good that you are checking the oil level, keep doing that. Before your trip, take the car to a mechanic and tell them the symptoms. They will likely check the actual pressure, the sending unit (pressure sensor) may be bad or your engine may be worn out. Fill us in on the mileage, maintenance history, check engine light status, etc

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Does the light go on only when idling?

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I would not go anywhere knowing that my oil pressure light is on. Get it checked out before you go.

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Thanks for the quick reply! The light comes on randomly when idling or driving. It blinks on and off real fast and will sometimes stay on for a few minutes and then turn off for a few minutes. There are no check engine lights on. The only major maintenance done is I had a new fuel pump put in at the beginning of 2016. The dealership replaced the bottom transmission pan (I think if thats correct) At the end of 2016. Other than that just regular oil changes and fluid, tires etc. I also had the breaks changed twice. I had diagnostics ran on it and it said low voltage to oil pressure sensor.

What engine do you have? Some V-6 and V-8 engines have a screen just under the oil pressure sensor that needs to be cleaned/replace every couple of hundred thousand miles. Generally if the oil pressure sensor is at the back of the engine, just under the intake manifold, it will have the screen as well. The screen is there to keep any pieces of junk from getting into the lifters.

Also, does this mostly occur when you are getting close to needing the oil change and then go away for awhile after the oil change? If so, the oil pressure bypass valve (OPV) may be stuck closed or blocked. Your oil filter is getting clogged up and oil can’t bypass. If this is the case, change your oil first sign of low oil pressure.

Edit: you might need a new oil pressure sensor.

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If the engine has been well maintained and not damaged by low oil, low coolant, etc., a new oil pressure sending unit is probably the answer. It’s usually not expensive. It’s a fairly simple matter to unscrew the old one and screw in the new one.

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I agree, replace the sending unit.

How many miles?

You probably need a new oil pressure sending unit, but actually you don’t since there is no point given the fact that if it does do its job you’ll just ignore it.

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Before a long trip and if the car were mine I would have an oil pressure test done with an external gauge.

An engine can run fine with low oil pressure…up to a point. If there is excessive wear in the crank bearings the last thing you want is for a rod bearing shell to decide to change its allegiance and move to the other side. That means suddenly and with a catastrophic bang followed by the need for a new engine.

The low voltage to the sensor could certainly affect the gauge reading but I would want to know what the oil pressure actually is.

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Agreed that it’s probably just a bad or failing oil pressure sensor… but I’d have the oil pressure checked manually by my mechanic, just to be sure.

Remember that you can have an engine full of oil…but if the oil pump is not working, then you can still destroy your engine. That check engine light is trying to tell you something.

Get it checked before your trip, just for peace of mind.

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It’s good that you asked. It seems that you either 1) have low oil pressure (at least intermittently) or 2) a gauge problem.

If the former, even when the light is out the oil pressure might be running just slightly above the sensor’s limit which also wouldn’t be good, could be accelerating engine wear, and the problem could get worse either gradually or suddenly. How will you determine when to stop, and will it then be too late?

If a bad sensor, you might not have an immediate engine problem but you also won’t have a reliable oil pressure sensor and if/when you do lose oil pressure you might continue to ignore it.

I’ve experienced both.

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Chevy Monte Carlo Low Oil Pressure: Diagnosis and Causes | Drivetrain Resource (700r4transmissionhq.com)

Service bulletin…

temp.xml (nhtsa.gov)

Here’s a thought . . .

Unplug the electrical connector for the engine oil pressure sensor

Is the connector oily . . . as in engine oil?

If so, the engine oil pressure sensor is literally blown and needs to be replaced

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And while it’s disconnected, clean its electrical connections before you plug it back in.

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This is located under the oil pressure sending unit as I mentioned above.

I had a car like that its was a different make and model but the problem was the oil pump it was getting old and not pumping the pressure needed at idle, I just installed a new pressure gauge under the dash and I could watch it closer but the engine held up it was more of a peace of mind thing getting the gauge. I would follow the manufacture service bulletin.