No!!! Do not run low on oil ever. If it’s lower than full when you check, top it up to the full mark on the dipstick.
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Some vehicles have a low oil pressure warning light only. That’s probably the light you are seeing when the engine stalls. When the engine stops running, obviously there’s no oil pressure because the oil pump is no longer pumping. Some cars have a low oil level light too. It comes on when the oil level gets low. Your car may not have an oil level light (I don’t know), but that would explain how the oil level could be low, and you get no warning light until the engine stalls.
Whether or not the low oil level (and subsequent possible low oil pressure) is causing the engine to stall, I do not know. Honestly, I kind of doubt it. I think the stalling is probably a separate issue (like possibly the throttle body needs cleaned like I mentioned earlier). But the low oil level is the more serious issue.
Yeah - no - I didn’t mean that low!!
thanks @Scrapyard-John - it turns out the Rav4 (2015) does Not have a low oil level light; only low oil pressure warning light - which did not seem to work in this case. I agree that low oil should not shut the engine off and will continue to investigate. Will post anything I find as continuation to this thread for future reference.
for now - thanks for you help.
If there was minimal oil pressure the warning light will not illuminate. If the low oil pressure warning light illuminates engine damage begins.
When the oil level is very low, the oil pump is pumping foamy engine oil, air and oil mixed. The valve lash adjusters will not operate properly with air in the oil, valves will not open properly.
When do you plan to pick up the vehicle to see if it runs properly?
That is for the Rav4 - She also has a Subaru that she said the light comes on when she lets the oil get too low.
I think you’re still confusing oil level with oil pressure somewhat. The oil pressure can still be good with a low oil level. Once the oil level gets low enough, though, the oil pressure will drop. That’s when you will see the low oil pressure light (other than when the engine is off, ignition on). Damage is done to the engine at that point.
The oil light could potentially come on for two separate reasons. First the amount of oil in the crankcase (the oil level) is low; second the oil pressure that comes out of the oil pump is low. What triggers the oil light on your particular car, don’t know. But your shop should know that.
You understand I’m sure how the oil pressure could be low if the oil level was low. But you might reasaonably wonder how the oil pressure could the low if the oil level was correct? That would happen for example, say if the oil pump was faulty, or if there was an obstruction in the oil pathway, or if engine damage resulted in worn bearings. The oil pump forces oil to the bearings via passages that are designed to leak a little. If they leak just the right amount the oil pressure will be correct, but if the leak too much the oil pressure will be too low.
Even better, your owners manual.
Most commonly, the oil warning light warns of low oil pressure. Your manual will probably advise you to pull off to a safe place and turn the engine off ASAP.
Good discussion - thanks for all the added conversation. But I think we are getting lost again. First - forget I mentioned the Subaru - it seems to be messing things up!
I picked up the vehicle this afternoon. So far it’s running fine - hasn’t shut off, but then it wasn’t a ‘constant’ feature everytime I stopped. Nevertheless, some things still don’t make sense to me; and sometimes I like to beat a dead horse 
Also - I want to state that, according to local toyota dealer and the manual, the oil light on the 2015 rav4 is Only for oil pressure, Not level. So my Q re: why the oil light didn’t come on with low oil is the wrong Q. Apparently there is no indication/warning for low oil level on the Rav4 (bummer - and misguided, I think, but I digress).
I am making the assumption here that super low oil = low oil pressure. If that is not an accurate assumption. then all this may be irrelevant. If that IS accurate . . .
The ultimate Q remains: is the Rav4 designed to shut the engine off (at a stop sign/light) when the oil is super-duper low? (Apparently, cuz it hasn’t done it again, but I’ve only driven @ 20 miles, with 3 lights). If so, why would the system allow the engine to restart with such low oil and hence pressure? I mean if toyota designed a safety for low oil and pressure: to shut the engine off before damage occurs - the car shouldn’t start again until oil is added and pressure is returned. but it does start.
this makes no sense to me. What’s the point in having a low pressure oil warning light if it’s not going to illuminate until after you begin to damage the engine! And since it only ‘flashed’ just a second before/when the engine shut off - well - it just didn’t occur to me that the problem was the oil level.
My head hurts! I can consider this a closed issue - and stop beating that horse - unless you really want to chime in.
Otherwise: Happy Labor Day Weekend - Stay safe
When the engine stalls, the low oil pressure light will come on because there’s zero oil pressure when the engine isn’t running. I think that’s what you’re seeing here. If the engine was shutting off to protect itself from low oil pressure, it probably wouldn’t restart immediately (like you said).
I agree that a low oil level light is probably more useful than a low oil pressure light most of the time. But if you check your oil pretty regularly, you don’t really need a low oil level light. The low oil pressure light is more useful for telling you there’s a problem with the engine. Like the oil pump failed, for example. The idea is that the light comes on, you shut the engine off immediately, you tow it somewhere, they repair it, and you never see the light again. It’s not meant to be a reminder. It’s more of a “shut it down, now!” light.
No, there is no system in place to cause the engine to stall, that would be hazardous. Low oil level caused the malfunction that caused the engine to stall.
When the oil pressure warning light illuminates, the driver is supposed to switch off the engine if possible to avoid engine damage.
I guess we can count on you to check oil level on a regular schedule now .
there are at least 4.75 qts of oil in there. if you lost that much, your driveway/garage would be swimming in oil.
I’m not even going to ask when the trans fluid/filter, anti-freeze, and brake fluid were changed last.