On my 2012 the piston rings are no good, or at least that was the theory years ago from a mechanic to explain why the car was burning oil, and thus I've been using heavier oil and topping off whenever oil gets low, between twice a year oil changes. The other day I found there was no oil on the dipstick. No idea how long I'd been driving like that. Immediately bought and put in oil. But I nearly poured the whole 5 qts in and still nothing on dipstick. So... 1. Is it because I need to drive the car a bit to see the oil register? 2. Do excessive summer temps burn up your oil quicker? 3. What is the potential harm to my car, and if it's running okay, did it get by without the oil by chance?
You put in 5 qts and it's not reading on the dip stick???? That can't be. It is 4.5 qts for an oil change. Running with no oil, will seize the pistons, and ruin the motor
Check the oil pan plug and oil filter for leaks. They could come loose if the oil change place didn’t tighten to torque specs. They can unscrew over time from vibration, and no there won’t be significant leaks on the ground because on top of The panels, there are spongy materials that will obsorb oil.
You've got it under control . The ole piston rings are it. No worries . Hold what ya got till ya can't. You do have extra car ???? Welp ya will soon.
Asked and answered. I will add in a non-threatening or chastising manner: You mentioned twice-a-year oil changes, which is not horrible unless you drive 20,000 miles a year in which case I would advise you to change your oil twice as often as that. Start monitoring your coolant and MAKE A PLAN for the Prius Death Rattle. It's not a matter of 'if'...... Best of luck!
What's the miles? New pistons/rings? Or for expedience, new short-block? Definitely get the overhaul gasket kit too.
No way it'd take oil more than seconds to make it's way down to sump. @rjparker's thought about the oil being too clear to read? A tip for reading the dipstick: pull and wipe it, and wait a few minutes before reinsert for the check: oil tends to be drawn up the dipstick tube, confuse things. Just over 100k? That's a little early, more typically 150k. What oil change interval?
If the oil is not in the sump or on the floor you may have poured it into the wrong place. Simple as that.
The Prius Death Rattle is an issue that is so common that the briefest of Google searches will fill you in. It's basically a fatal design flaw with the G3 Prius that results in blown head gaskets in a significant number of these cars. One of the things (IMHO) that exacerbates this flaw (EGR cooler/valve) is infrequent oil changes that allow more combustion residue to gather in the usual places. Oil has more than one job. Another aggravating issue (IMHO!) is excessively long oil change periodicities and insufficient sump volume - which are additive, and a 'closed hood' maintenance culture with Prius owners. You're obviously checking your oil - hence this thread. If you're knocking down 12,000 miles a year and doing bi-annual changes then you're beating the house odds for maintenance - PROVIDING that you're checking your oil level every 1000 miles more or less. If I had YOUR car - it would be MORE for both checks and changes...... YMMV. The rest you will suss out as you go. Read a LOT. Believe some of it. There's a YouTuber and forum member named @NutzAboutBolts who can give you MUCH MORE info and I would strongly advise you to 'like, comment, and subscribe!' to his channel. My opinions are my own. Disclosures: I've logged somewhere around 150,000 miles on TWO G3s both company Cars, and each survived well into the 200,000 mile club. I've never OWNED a Prius - or ANY Toyota since the late 80s and despite swearing a blood oath that the Earth would be orbiting a cold dead star before I would EVER buy another one I have tried twice since joining this forum to break my oath. Fortunately? Toyota Southeast saved me each time.... Good Luck! Stern Shot: Share your honest experiences without fear of criticism! Don't be afraid to be wrong. If you're human - you WILL BE at times. The world NEEDS more honest on-line brokers. If you never take any flack, then you've probably never been over the target......
Just a data point for the OP, our 2011 Prius is edging up to 150K (149,9XX) on the odometer and is not burning oil, ... yet. The oil has been changed at 5K/mo intervals regularly with 0w-20 Mobil 1. The EGR circuit and intake manifold were cleaned at approx 120K when the sparkplugs were changed. An oil catch can was also installed and it's collecting a fair amount of oil between oil changes. Regarding the oil dipstick situation, the oil registers almost immediately on the dipstick after being added to the engine at the oil cap.