Recently did a bit of work on my new to me Prius. New plugs, coils ,EGR+cooler, intake manifold, and pcv. Used a borescope to peak at the pistons. I'm not a mechanic, so anyone have opinions on the condition of my engine? Sorry for the potato quality. Cylinder 2 and 3 were closest to TDC. Past that, no clue on which is which.
Looks like you're burning some oil on 2 of them while the top 2 seem almost too clean like they getting washed with coolant.
Really hard to judge. It would help if you could keep track of which cylinder is which. Maybe too, crank the engine (manually, using bolt on end of crankshaft, at right end) so that each pic is at bottom-dead-centre. And focussed. What’s the miles on it? How recently acquired? How’s it running?
I would not be happy with that going on inside of any internal combustion engines that I own at the moment I can say that I mean if it was running correctly and not making a racket and all of that I might run it until I could be through with it but if it's one of my keeper vehicles I'll move over to another one and put this one in the bay and have a look at it when I have time that's why I have several generation twos so we're never under the gun and out of transportation that's when you make foolish decisions quickly and waste piles of money.
From the pictures alone; I'd guess that this motor has high mileage and hardened valve guide seals. This allows oil to drop into the combustion chamber causing that black tar on the piston heads. Even on the clean piston heads, you can make out the trail between intake and exhaust valve. I believe 'v sport wagon' is correct; there's probably a head gasket issue or someone has temporary patched it with some chemical head-gasket sealant - so they could sell the car. If the car is running OK now, there's no telling how long that sealant is going to "hold-up", assuming you don't run into cooling system issues (sealant partially occluding your cooling system). Luckily were going into the winter months, so your probably good til next spring or summer. Sorry for the bad news. You asked for opinions and I wouldn't have touched this one, unless it was FREE. That's assuming that everything else is in pristine condition.
Hey all, appreciate and thank you for the advice/opinions! I've had it since December of '23, and have put roughly 12k miles on it in that time. It's at 197k currently. Interior is immaculate. Underside... Is less so. Before I did the engine work I replaced a few failed rusted hard brake lines, including one of the long ones that runs under the car. It's my first snow vehicle - so the amount of rust was shocking for someone used to California vehicles. So far, there have been no coolant or oil consumption issues, no overheating problems either - my 40 mile commute is 39 miles of straight flat driving so maybe that helps. Averages around 45mpg after the work completed above; which was triggered by misfire and EGR codes popping up. It had a seized EGR valve and pcv. Now about once every 1200 miles there's a temp code (no CEL, just observing on OBD2 scanner) of misfire on cylinder 2 but it clears after another day of driving. If it makes it until this winter I'll pull the head and if it hasn't warped I'll go through and freshen up the valvetrain. If damaged has occured it'll either be a head swap or I'll swap in a 2014+ engine. ♂️ It's my first Prius and didn't have many options when I started looking for a commuter, but even running the way it is it beats the other option - a 14mpg F250.
You're in Western New York? Generally there anything made today that doesn't have a heated and cool temperature controlled garage in those areas is maybe a 5-year car if you're lucky My Corollas and upstate New York would eat up brake lines pretty quick and back in those days that was something I wasn't really willing to replace and they were very costly to buy this is like 1985 '86 83 in that area these parts were a lot more costly then before the internet really took off and all that so usually I would just come down south or lots of my family lived by corolla's down in the south take them up north turn them to salvage in 3 years or so go back down south where family still lives by another one or two Corollas drive them back home this went on quite a while because up there cars just disintegrate. Then I moved down south because I got smart and wanted to get out of that permanent shoveling snow and nonsensical weather and taxes were rising up north and everything was going really crazy and everything was almost free down here when I moved here quite hysterical I'm never look back now the four cars that I have will last forever just from not being someplace.
They look nasty like mine did, when I was doing my B12 piston soak. On the 3-4th soak cycle, I had to blow out the pistons with a air compressor because the engine was locking up. So far, it seems like I've completely solve my oil burning. Your piston rings and oil holes probably look just like that.
Hi all, just wanted to post a follow-up to this. I eventually did the head gasket after the inverter water pump gave up the ghost in february. It took me about 12 hours over three days in sub-freezing temperatures in my driveway. Had I just tackled this in the summer or fall I probably could have done it leisurely over 2 days and about 8 hours. Here's some photos for funsies - I've put about six thousands miles on it now and haven't had any issues - no coolant or oil consumption issues and absolutely no rattles on start up. Feels good. 20250102_150133 by Mkgcb posted Apr 8, 2025 at 8:12 PM 20250102_150129 by Mkgcb posted Apr 8, 2025 at 8:12 PM 20250111_152202 by Mkgcb posted Apr 8, 2025 at 8:12 PM 20250111_152157 by Mkgcb posted Apr 8, 2025 at 8:12 PM
Yeah none of those links work this is a pain in the nice person place to post pictures and make all that happen Don't know why don't care Just seems to be weird some people get it they know how to adjust their photos do whatever needs to be done I don't even try.
for the pics, just click the upload a file button, it shouldn’t be hard. Are you on a phone or computer? sub-zero in driveway, ugh. Did you have any heater(s)?
Thanks for the tip! I was posting this on a PC but not always paying attention to the little buttons everywhere. Had a heater I'd go and warm back up on but was just a little 1300w thing.
In the photos the inside of the engine is heavily coated with varnish. What oil do you use and what is the maximum mileage you use before changing the oil?
Just as a preface I bought the car at the end of 2023 when it had 188k miles. Had a semi-decent service history at a Toyota dealership but didn't come with any documented oil change history. Since, I've done oil changes every 5k miles with 0w-20 and most recently 0w-16. Typically using mobil 1 high mileage full synthetic.
