Oil Monitor System

[Jimailer]

Does anyone really know how it works? What is it looking at and how does it do it? Should you do oil changes as it tells you or how often is best. Normal driving, not racing at all ( Well almost never at the red line )

[c4c5specialist]

HI there,
Your oil life monitor takes into consideration all driving conditions and engine loads, puts it into a mathematical formula and then give you an oil life percentage remaining.
The engine control module factors in engine rpm, engine load measured by the manifold absolute pressure sensor and throttle position sensor, coolant temperature sensor, vehicle speed, engine running time for that ignition cycle, and mass air flow sensor readings, to determine exactly how the engine is running. This, in conjunction with the internal information in the module that you are running synthetic engine oil, is factored into the formula and it give you the total on your DIC.
This is an extremely ACCURATE way to measure your effective oil life.
Allthebest, c4c5

[Jimailer]

Thanks I knew the car was smarter than me but did not know how it did it.

[SilverFox]

Originally Posted by c4c5specialist

HI there,
Your oil life monitor takes into consideration all driving conditions and engine loads, puts it into a mathematical formula and then give you an oil life percentage remaining.
The engine control module factors in engine rpm, engine load measured by the manifold absolute pressure sensor and throttle position sensor, coolant temperature sensor, vehicle speed, engine running time for that ignition cycle, and mass air flow sensor readings, to determine exactly how the engine is running. This, in conjunction with the internal information in the module that you are running synthetic engine oil, is factored into the formula and it give you the total on your DIC.
This is an extremely ACCURATE way to measure your effective oil life.
Allthebest, c4c5

All excellent information however it does not factor in dusty conditions in the area one is driving. No matter how good Mobil 1 might be in regards to oil breakdown due to heat ect., ect. the oil will still get dirty and cause eng. wear therefore use your own judgement. My understanding of Mobil 1 is that it is CAPABLE of 15k oil change intervals however there is no way I would wait that long. I have elected to change mine at 5 or 6k.
Think about your driving style and the environment were you drive to come up with your own oil change interval.

[c4c5specialist]

HI there,
Dusty conditions with a 10 or 30 micron GM filter and the fact that the crankcase is a sealed unit, except for fresh air taken in AFTER the air filter.
That is one of the reasons stock air filters are so important and it is NOT as much of a factor in oil change intervals.
Allthebest, c4c5

[abc]

Originally Posted by c4c5specialist

HI there,
Your oil life monitor takes into consideration all driving conditions and engine loads, puts it into a mathematical formula and then give you an oil life percentage remaining.
The engine control module factors in engine rpm, engine load measured by the manifold absolute pressure sensor and throttle position sensor, coolant temperature sensor, vehicle speed, engine running time for that ignition cycle, and mass air flow sensor readings, to determine exactly how the engine is running. This, in conjunction with the internal information in the module that you are running synthetic engine oil, is factored into the formula and it give you the total on your DIC.
This is an extremely ACCURATE way to measure your effective oil life.
Allthebest, c4c5

So you are saying it is fine to go with the OLM till it tells you that you need to change oil?

[c4c5specialist]

Yes.
Allthebest, c4c5

[abc]

Originally Posted by c4c5specialist

Yes.
Allthebest, c4c5

[c6patrick]

I had my oil changed last week, showing 17% remaining. (It was time mileage wise). I watched the guys drain and add fresh oil, as I get nervous when anyone is near my baby. The monitor afterward still showed 17%. about 800 miles leter, it is at 12%. Any ideas ????

[c6patrick]

Originally Posted by c6patrick

I had my oil changed last week, showing 17% remaining. (It was time mileage wise). I watched the guys drain and add fresh oil, as I get nervous when anyone is near my baby. The monitor afterward still showed 17%. about 800 miles leter, it is at 12%. Any ideas ????

Duh, in an exhaustive search of the owner's manual (1.2 minutes) I have reset my Oil Life Remaining to 99%. Sorry to be one of those guys..... But this brings up a question of the accuracy of the monitor. It seems to me that it is more of a simple timer rather than a complicated computer controlled driving conditions monitor. If it was actually sampling oil viscosity, my values would have changed with the fresh oil. I won't put any faith in that gadget and I will change oil at mileage intervals no matter what that reads.

[Mark Watkins]

Originally Posted by c6patrick

I had my oil changed last week, showing 17% remaining. (It was time mileage wise). I watched the guys drain and add fresh oil, as I get nervous when anyone is near my baby. The monitor afterward still showed 17%. about 800 miles leter, it is at 12%. Any ideas ????

The moniter needs to be reset. The instructions are in the owners manual. Mark.

[Patrick]

Originally Posted by c6patrick

Duh, in an exhaustive search of the owner's manual (1.2 minutes) I have reset my Oil Life Remaining to 99%. Sorry to be one of those guys..... But this brings up a question of the accuracy of the monitor. It seems to me that it is more of a simple timer rather than a complicated computer controlled driving conditions monitor. If it was actually sampling oil viscosity, my values would have changed with the fresh oil. I won't put any faith in that gadget and I will change oil at mileage intervals no matter what that reads.

The oil life monitor, if I understand it's operation correctly, isn't necessarily monitoring miles driven. And I don't believe it's got a sensor that monitors oil viscosity. What it's doing is starting with the assumption that when you reset the monitor after an oil change, it's 100% new oil you've put in, and then using variables such as mileage driven, average speed you've been doing, operating temperature, and whether you've been doing more highway driving or in-city (stop and go) driving, to determine oil life.


-Patrick

[Hib Halverson]

The OLM looks at two data parameters. They are: engine oil temperature history since last reset and number of engine revolutions since last reset. It takes that data, applies the OLM algorithms (they skew the drain interval according to the oil temperature history) which GM Powertrain has been developing since 1990, then turns on the oil change light on when the programming deems it necessary.

There are three factors in the oil change interval decision that the OLM does not consider:
1) calendar.
2) operation in dusty environments.

Thus, if your car gets less than 10,000 miles annually, you need to change the oil once a year, regardless of mileage and, if the car is operated regularly in a dusty environment, change the oil every 3000 miles.

The OLM in a Corvette is accurate when the engine is lubricated by 5W30 or 10W30 petro-based oil (90-91) or 5W30 or 10W30 Mobil 1 (92-09). Anyone who decides to ignore the system and set their drain interval by simple mileage is either wasteful--if they use the (ancient-but-well-marketed) urban legend of oil changes every 3000 miles even when not operated in a dusty environment--or foolish--if they continue to run the engine w/o an oil change for a significant distance after the light comes on.

In addition, there are two less-likely scenarios when the OLM will, also, not be accurate: if either 1) a lower quality oil, such as a cheap petro-based product rather than Mobil 1 5W30 or 10W30 or 2) a better quality oil (such as an ester-based synthetic) is used.

[Patrick]

Thanks, Hib. That's very useful information to know.

-Patrick

[Tuna]

It still seems a lot like "FM" to most people. You either believe it or you don't. If you don't you do something different (whatever you've been doing before). I do something different.


Before you ask: "FM" - F#$%ing Magic