Hello,
I have a 2010 toyota prius that burns about a quart of oil every 400 miles. It also knocks every now and then but then goes away on its own.
Can I try the new gf6 oil on it? 0w-20 is the oil recommended. Can the gf6 oil help with the oil consumption?
Also, should I try replacing the spark plugs to prevent the knocking? Original plugs as far as i know.
No oil leaks and coolant is at consistent level.
174,000 miles
Added note. PCV Valve has been replaced in within the year.
No codes. I don't have a fancy scan tool though.
The auto zone scan tool doesn't show anything.
How long has it been since the PCV valve was replaced? Are you sure it's burning (are there any leaks)?
Is the knocking a deep thudding sound (rod knock), or a light tap (valve noise)? Or, is it a clacking type noise that happens only when the engine is cold (piston slap)? Any codes? It would be helpful if you could upload a video demonstrating the noise to youtube or a file sharing site and post the link here.
PCV Valve was changed early 2021. Didn't have any effect towards the two problems.
I will work on getting a video uploaded. But I would say it's a deep thudding that makes the engine move back n forth. No codes. I don't have a fancy scan tool though.
The auto zone scan tool doesn't show anything.
It's likely that your engine mounts are worn and loose and it's the rocking of the engine that is making the noise. (Bottom end engine problems are rare on Toyotas unless they have been seriously abused.)
Added video.
https://youtu.be/97JvttJb2ok
That is not a good sound but sounds more like accessory drives than something internal to the engine. (Rod knock is typically a slow, heavy thud that increases with engine load and valve noise is a light, fast tapping.) I'm not familiar with the engine setup on the Prius though, maybe one of the guys who is can comment on what's causing that. For now I would avoid driving it until the noise is identified.
Listening to it again and thinking about it, this is sounding more like engine bottom-end noise. Given that it's been burning oil at a prodigious rate, how low has the oil gotten? Low enough that oil pressure dropped and damaged bearings? It only takes a fraction of a second with the engine under load to score up the bearings if there's little or no oil pressure. Has oil pressure been checked?
Probably a bad rod or main bearing at this point. New engine. It's too late for oil or spark plugs to help anything.
Are you seeing smoke in your exhaust? If you're consuming a quart of oil every 400 miles with no leaks, there should be smoke coming out of the tailpipe at that rate, usually it's a bluish color. Get a paper towel and wipe the inside of the tailpipe. If it's slimy, it's burning oil, which means your engine's pretty much worn out from lack of oil maintenance. In the off chance Chuck is right about bad motor mounts and a leak as the noise and problem, toss some UV leak dye for oil in, it's $8 at AutoZone, and grab a UV leak dye kit with a light and glasses and look around underneath and above the engine for dye.
Maybe try replacing the PCV valve and pray it does something otherwise your engine is probably on its last legs, it would not be worth fixing it. If the PCV valve replacement doesn't work, I would probably just junk the car.
Try cleaning the EGR.
I am assuming your problem is at startup. EGR gets dirty over time, and it can get stuck open or closed (I forget which way.) Somehow it messes with startup if it is stuck open, causing those crazy sounds. Or you may need to replaced the EGR, if it is too far gone.
Don’t junk the car just yet. I’d try cleaning first.
Let us know how it goes!
Wishful thinking. I guess it's OK to hope for the best but expect the worst.
The way that engine is running it’s junk and nothing can really help as I see it.
I’d try getting a junkyard engine, call all of the junk yards in your area and see how much it’d cost (it ain’t a mechanic or a dealer, you can usually negotiate. Usually you’d be able to get them down to a few hundred for parts and another few for the install, that’s a common car and demand on those engines is low, from my experience)
also that being an 11 year old hybrid - I wouldn’t put any real money into it, it probably doesn’t have much life left in its batteries and those aren’t cheap at all.
My 2013 did that to me a couple of times on startup. The first time it had been sitting for two weeks at the airport, and when it starting knocking I immediately shut it off. Started back up a few seconds later and it was fine. It did that maybe two times while I had it for 5 years and 100k miles, and I sold it at 180k running perfect, and not burning enough oil to mention. I looked up that issue and it seemed to be kind of common to randomly get it, so I ignored it.
May I ask how long you have had it, and at what mileage? Very strange for that generation prius, or the older 2nd gen prius to have much of any engine issues.
