mlevk

My Oil Level Light comes on every now and then
when I am at Highway speed. The level is fine though.
Does anyone else ahve this problem and is it the
"sending" unit that is malfuctioning?

Rollin

That happend to me too, it was 3am and in the middle of nowhere on a KS intersate. I was coming home from a week long ski trip in Colorado. I pulled over and checked the level it was fine, it happend twice that night, both times I had the cruise set close to 90 mph, hasn't happend since

FusionMan79

I started having that problem a little bit too. The light would come on and go off when the road tilted. I believe the oil light comes on when you are about a quart low. So even though your level may seem fine it might be that you are about a quart low. See if it keeps happening after your next oil change. When my light started going on, I added a quart and never had it go on again.

mlevk

Thanks guys,
isn't the 1 qt low at the bottom mark of the oil stick?
If it isn't then I might be low but I really don't want to overfill the oil either , I guess I'll chnage the oil a little early.

bobkon_ls430

From my past experience, the oil sensor on an engine measures oil pressure, not necessarily oil level. Though if your oil level is low, your oil pressure would be too low. If you overfill your crankcase, you could have too much pressure, which could also damage an engine.

In an engine, there is some type of internal oil recirculating pump, usually gear driven, sometimes from the distributor and has an oil pick-up that draws oil from the oil pan. The pick-up tube or pump inlet usually has a mesh grating over it to keep from sucking up any large particles or sludge. If one of these is clogged or an oil gallery is blocked, or not working at its optimum, you could experience low pressure under load, or higher RPMs. It may be sufficient at lower speeds or idle, but maybe not sufficient at higher speeds.

Definitely check your oil level. It should be between the two marks on the dipstick, never above the top mark. Anywhere in between is fine. When it gets down to the lower mark or below, it indicates its time to add a quart, which may not necessarily bring it to the upper mark on the dipstick, but if its somewhere in between, thats ok.

Oil pressure sending units can certainly go bad, too. Its the next simplest thing to check. Service manuals usually have a test procedure to test it in or off the engine. The on board diagnostics may also check. I have replaced faulty oil pressure sending units, and have found they usually just go bad, not just when you're driving at highway speeds. The sensor is typically on the side of the block.

I would definitely let a good mechanic, either at a Lexus dealer or independent, diagnose it for you. Compensating for low pressure with more oil could cause damage to the engine.

I hope you are able to figure out what it is, and report back to the board. I hope this info is helpful.

Take care,

bobkon_ls430

mlevk

Thanks Bobkon_ls430

Mine is a 1991 LS400 , sorry I didn't mention that before.
There are actually 2 warning lights for the oil.

1) Oil Pressure , it did not come on. upper right side of gauges.
2) Oil Level, so says the manual. lower right ,That's the one that came on for a short time.

I take it you have a LS430 ? I am sure it's a beauty.

bobkon_ls430

Hi Mlevk,

It's much better its the oil level indicator and not the oil pressure light. Seems to be more of a courtesy indicator and early warning light than an indication something has gone wrong. Should probably still test the sensor and replace it if its bad.

You're right, I do have a new LS430, and it is very nice. I've had it since the end of April, and has close to 4k miles on it, and I still get a little paranoid though parking it in crowded lots. Lexus doesn't put a lot of body side molding protection on their cars, and the sheet metal seems a bit thin. So for now I park out in the boonies.

Its in a new color this year, parchment crystal with the ivory interior with birds eye maple trim. Did not get the ultra luxury package, I felt my children who are six and three didn't need all that stuff in the rear. I could only imagine a Capri Sun juice pack spilling all over those rear controls. Now, if I had a child who was old enough to drive, I would have definitely ordered that package so I could sit in the back with the old lady and relax with the massage seats. I did get the Mark Levinson audio package with navigation and Lexus Link systems.

Well, I hope you get the oil level problem figured out and that nothing is wrong with your engine.

Take care,

bobkon_ls430

blkstealthpaid4

I am not sure which light comes on but it is located on the right bottom of the instrument panel and it stays on until I reduce the speed to below 85mph.This starts at exactly 85mph.I also did check the oil gauge and my uncle suggested replacing the filter.I also noticed the car was also filter-sensitive.My first was Fram which was wack as hell.I changed that to PL etc...part # and this was purolator.That helped a lot and I only saw that light come on just once after that.I have finally decided to just get the $6 oil filter from the dealer when I change my oil.I think the lexus filter will have more bigger inlets for oil flow than these aftermarket filters.