Hello, I have a 2013 Prius 3 with just under 230k miles on it. I've noticed that as I get to around 4k miles since my last oil change, I've somehow lost enough oil that taking corners sharply will briefly blink on the "oil pressure low" message. I remember last time I put in about 2/3 of a quart and it seemed to stop the issue, but as it's starting to come up again (I have some oil to put in it, just haven't gotten outside to do it while the engine's cold), is this unusual for a car of this age? And if so, where should I look to figure out what's going on before it gets worse? Thank you.
Have you ever cleaned/had work done on your EGR system, intake manifold, and/or your PCV valve? How's your coolant level, stable? Any rattling, or knocking, on start-up? Any engine error codes(lights) that you've had diagnosed? If your oil level is low, be sure to add oil, checking the level often. Welcome to the forum! You're in the right place.
no, it is very common for a car with that mileage. what's unusual is for a car of that age to have that much mileage
Yeah, by the time you get the low oil pressure warning (typically when cornering), you're into dangerously low oil territory. I would check the oil immediately, with the car on level ground, bring it right up to the top mark. And start checking and topping regularly. To make the dipstick easier to read: 1. Pull the dipstick and wipe it, and wait, about 5 minutes. With the 3rd gen at least, when you pull out the disptick it tends to draw oil up the tube, which can make reading the dipstick hard, smears oil all along the edges. The wait gives that drawn-up oil time to drain back down. After the wait, reinsert the dipstick fully, pull it out, and hold it horizontal in a good light. 2. The face of the disptick towards you (as you draw it out) tends to be clearer/cleaner than the far side. 3. The distance between the two marks represents 1.6 US quarts (1.5 liters). With your consumption rate, I would always aim to top up to the full mark.
How fast do you drive? Mostly highway, city, or combo? A 80% of my driving in highway. When I stay 65mph, I use about 3/4 of a quart between 10,000 miles changes. When I drive 70mph, It doubles. And my mpg's go down about 5mpg.
I've never cleaned or had work done on any of those, and I don't believe the previous owner did either. My last oil change I took it to the dealership because I was working 60-hour overnight weeks and couldn't be bothered, and they could see that the previous owner had taken it in for oil changes but noted that the spark plugs were original and that I should get them replaced. Coolant has been fine, no start up or engine codes so far. Right now it's mostly city, but it's just like 10 minute drive to work and back. August and September I was doing ~700 miles a week, primarily highway, and similar again in December for work. Highway driving, I usually go 75mph because I don't like how much more my mpg went down doing 80, as it is I typically get 42mpg. I've been doing oil changes at 5000/whenever the oil change indicator comes on. I've never been much of a gearhead (in part because of my dad being weird about gender roles), but it's something I want to learn, especially now that I feel like I have the time and energy combo to try learning to work on my own dang car, especially since it's such a financial investment.
First off, welcome! Secondly, when the low oil pressure light comes on that is very bad -- it means your engine is being starved of lubrication which is likely causing irreparable damage. You need to add oil to your engine immediately -- as in, this morning before you drive it. I bet you'll need to add about 3 quarts to get the dipstick reading up to the "full" mark. That means you only have about a quart and a half in there now. To answer your question about where the oil is going: it's being burned in the cylinders then expelled out the exhaust pipe. Either because 1) the rings and/or cylinders are worn, or 2) because the rings are sticking as a result of carbon build-up on them. Neither of those problems is going to be remedied by a quick visit to the dealer. If you plan to keep this car, you need to commit yourself to checking the oil regularly. Depending on how much you drive, maybe once per week, or at every 1000 miles. If you're not willing to do that, then you're going to end up running the engine dry of oil and destroying it. That will require a new (or used) engine -- which will be thousands of dollars. As @ASRDogman suggested, the speed at which you travel makes a huge difference in oil consumption. You can cut consumption in half by traveling the speed limit.
NO, pretty much normal for that MILEAGE. Age isn't much of a factor. You need to check the oil more often. And you need to be sure you are reading the "stick" right. My guess is that you might need a full quart every 2K miles or so. Typically when the oil light starts blinking that is low oil PRESSURE, indicating that the level is dangerously low which would require a lot more than 2/3 quart to get back to full. Changing to high mileage oil on the next change might help some but there is no easy "fix" for a worn out engine.
WOW! Speed demon! That's where your oil is going. The cylinders are sucking in through the valve guide seals. Drive 65pmh and you'll spend a lot less on fuel and oil. And pretty much anyone can learn to work on any car.
