No oil warning or maintenance light

On two separate occasions I ran out of oil on my 2007 RX. Per service dept there was a leak in the oil cooler line and then the wrong type of filter was used and gasket missing. I was missing 5 to 6 qts. of oil. Gauges supposedly work under pressure therefore no light came on. Is this true?

The low oil pressure warning light only comes on if the pressure goes to ZERO. I doubt there is a low oil level warning light or gauge. The dipstick serves that purpose.

Didn’t anyone notice the leakage until the oil was gone? There must have been oil spots where the vehicle is parked.

Does anyone check the oil level on a periodic basis? This would have alerted you to the loss of oil before it was all gone.

On each occasion the car had been serviced two weeks before and there was no indication of any leakage. The only indication we got was a lag in acceleration power. We stopped, checked the dipstick and found there was no oil. Both times we had it towed to Lexus. The first time they said there was a leak in the oil cooler line and the second time they said the wrong filter was used and the gasket was missing. When we asked why no oil light came on they said that this is normal because the gauges work under pressure therefore there was enough oil in the oil pan for the light not to come on and that there was no damage to the engine. Other than checking the dipstick or lack of acceleration is there any other way to know that you are out of oil?

ANY pressure in the line and the oil light won’t go on. I know of two incidences where this happened EXACTLY as happened to you. Friends oil light did come on about 5 seconds before his engine blew up.

As for the filter…This vehicle doesn’t have a canister filter. All you replace is the paper element two gaskets. Was the filter a Toyota/Lexus filter??? If not that’s why the dealer is saying the wrong filter was being used. The new filter comes with 2 new gaskets (no matter who the manufacturer is…Fram, Toyota, Wix, Purolator). Both gaskets should be replaced when the paper element is replaced.

Other than checking the dipstick or lack of acceleration is there any other way to know that you are out of oil?

No,not really.

As you found out, the oil light is a pressure switch: if it’s on, it means that the oil pressure is too low to turn the light off. Since the threshold is quite low, this effectively means one has no pressure.

It’s especially important to check the oil immediately after an oil change, because of the possibility of any mistakes (we’re all human). In addition to re-checking the level the first couple times you drive it, the first time driving it, either get out with it idling and look for dripping oil, or just rev it for minute or so and check for an oil spot on the asphalt.

Take a page from the aviation industry: the plane isn’t “fixed” until the repaired part in question is tested in operation and found to work properly.

The lack of acceleration is a bad sign. Was there any indication of overheating when this happened?

Any leak that allows 5 qts of oil to disappear in two weeks should leave traces of itself. The lack of a filter gasket should have been apparent upon start-up.

It only takes a very small amount of oil to keep the low pressure warning light from coming on. I’m not sure I’d buy the dealer’s story that “there was no damage to the engine.”

I don’t like linking poor acceleration and no oil pressure. If your engine was showing a decrease in performance and the cause was determined to be low oil pressure then permenent damage has been done,but we don’t see that,you state performance is a designed.

I was trying to link low oil pressure and temporary loss of performance to a inop variable valve timing system but have not gone that far.

Are you saying your car has both a gague that shows oil pressure and a light that shows oil pressure and the light never came on and the gague read correct?

Or does your car have a light for oil pressure and a gague for oil level? Can you cler this up a bit.

One no oil condition was due to a oil line leak,line replaced all is well.

Next no oil condition is related to wrong oil filter canister element and incorrect sealing ring on canister top,leak fixed,all is well.

So can you rephrase your exact question? It appears you are asking “can a oil pressure gague read correct but the engine have no oil in it and in addition no notification from a oil pressure light”? I can’t make this out.