2005 Pruis using oil

Who changes your oil?

 

The PCV valve can make a difference to oil consumption, and as it is not an expensive item it is well worth trying.

John (Britprius)

 

I wouldn't worry about 2 quarts in 5000 miles. My 05 will use oil at different times and driving conditions with no rhyme nor reason. Back when there was 100.000 miles on the car, it used one quart during an 1100 mile trip and the same trip at 125,000 miles used only a few ounces. The only difference was the time of year. I noticed during winter it may use 1/4 to 1/2 a quart every few thousand miles and in the summer it usually never need oil between changes. I've always used the same oil filters and oil so that is not a factor, the PCV valve has been checked and cleaned several times but never sticky or clogged. I never let the oil level drop below a half quart and never go more than a few weeks without checking it.

 

I would go thru a simple process of elimination to narrow down the root cause before making any assumptions.

Based on your mileage, oil rings very likely are stuck from carbon build-up. Even the PCV valve could be stuck & need replacement, as both Priusgto & Britprius pointed out.

I ran into this with my last car (not a Prius) which lasted me 217,000 grueling miles, that car started to consume "excessive" amount of oil at 140k even though the car was dealer serviced w/ regular OC at 5K interval. But 1 quart of oil every 2k was above my comfort zone.

So I added a quart of Rislone additive w/ the OC and within 2000 miles the oil turned black! During the drain oil looked like black soup. Refilled the car w/ fresh oil this time w/ a quart of Marvels Mystery oil instead, took over 3k before oil turned black again.

After two sessions of cleaning w/ MMO & Rislone, the oil consumption stopped & I drove that car almost another 80k without any excessive oil consumption.

Word to the wise, if you decide to take this route, monitor the oil condition closely because it could sludge your engine & ruin it. I'd drain the oil & start over as soon as it turns black on you.

If that doesn't reduce consumption, at least you know rings aren't the culprit & you've done the engine a great service by removing the sludge/carbon deposit etc.

As for PCV replacement, member galaxee posted this DIY step by step page a while back which I found very helpful. Its a $12 part at most Toyota dealers but will take an hour of your time.

PCV replacement how-to with photos | PriusChat

 

On the side note, consider choosing a more suitable 5w-30 synthetic, one that has the least consumption volatility mass % loss index, aka "D5800 NOACK" index.

"Pennzoil Ultra 5w-30" is all I use in my Gen-2, because on top of being an outstanding synthetic it also has the lowest D5800 % loss index of the bunch at only 6.6%, oil consumption btwn OC is almost none existent, while the popular Mobil 1 has 10.1%, Valvoline Syn Power 11.6%, Castrol Edge 11.1%, Kendall Liquid Titanium 10.7%, Pennzoil Platinum 9.3% and Formula Shell 9.7%.

The "sleeper" oil of the 5w-30 bunch IMO is Quaker State Ultimate Durability( QSUD), its D5800 index is only 8.8%, at $22 per 5 qt jug at most Walmart it is quite a bargain for synthetics.

My first choice would be Pennzoil Ultra, while QSUD - Pennzoil Platinum- Formula Shell all make excellent second choices.

 

193,000 miles? It's wearing out like any other car....I mean I like these little quirky cars too but hell, they wear out like everything else. The rings are tiny in these engines and the oil is thin to boot. At what point are we satisfied that we have had value for money and we recondition or replace? These engines are very well designed to last but if they have a weakness, it's the rings. I've just rebuilt one and the only component to fail in 215,oookm was the oil rings, thats it. No other damage or wear that required machining or replacing anywhere in the engine, just a light hone and rings. Goes like new again. Plenty of punch and torque.

 

I have 2008 Prius, @163000 miles. June of this year I had dealer put synthetic oil in before coast-to-coast trip. Not really checking level until October; when found to be 2 quarts low! I am checking it frequently now. It may have been a unique occurrence. But was surprised that no other low-level warning was given on dashboard. (understand that low oil pressure IS signaled ) I probably have gotten complacent with the good performance of this hybrid. Curt

 

The only indication of low oil is a rather laconic warning on the MFD which says "Problem". It happens when making sharp turns or accelerating, leaving the oil intake dry for a moment. At that stage the level is quite low. So check the oil often like any other car at that mileage.

 

I would like to share my experience under this thread of my 2007 Prius starting to use oil. My experience is the same as drivesalot as far as my engine all of the sudden using oil. I had a brother in law that worked for Toyota and would always take my car with him to work for oil changes. He switched jobs and I lost this convenience!

I then took my Prius to a quick Lube where they talked me into using synthetic oil. It cost more and I love my car so I said yes... Just a few weeks layer my red triangle alerted with the oil symbol and I checked my oil stick and I was over 2 quarts low... I did not know why so I added oil and then took the car to get another oil change. I used synthetic again with the same result. Several weeks later I get the same warning.

I believe the cause to be switching to synthetic oil when my car was conditioned to regular oil.
I have since switched back to non synthetic oil and I will see what happens with the oil level.

One possible problem that resulted from the engine burning the oil is now my check engine light recently came on with a code P0420 error which has to do with the catalytic converter malfunctioning. I read that an engine burning oil can poison the catalytic converter and ruin it !
I can't confirm this problem, but all this I have described has happened in a 3 month span of time.

My car has never burned oil. I have never seen evidence of a leak. The engine must have burned it. Is it possible the synthetic oil did something to the oil rings?

If anyone has a similar situation please post here.

Thanks

 

After recently purchasing a used 05, I noticed it was using what I thought was too much oil.

I took it back and had it out with the dealer and they agreed to service it as the oil looked bad. They told me they put 25/70w oil in and a wynns additive to "reseal" the rings or something to that effect.

It's using 50% more fuel since. Is that normal? Do the rings have problems too with these? As I say, I'm not a car guy, the rings seal the oil in right? Any help greatly appreciated.

Thanks again.

 

Please post your location Derek. 25w70 is a ridiculous viscosity grade to put into a Prius. Assuming that this isn't a troll post then the answer is that the dealer is doing crazy things to dishonestly try to mask the oil usage problem.

Please specify the rate at which oil was being consumed with the recommended 5w30 grade oil.

I'm guessing you're not in the US, I'm sure they rarely if ever see 25W70 engine oil there. Are you in Australia by any chance?

 

No, US and yes, I'm genuinely in need of good advice. I agree that I'm being taken for a ride. I don't know what was in it before. I have done some more reading since and yes, it say's clearly that it does not take heavy oil. It sounds like something you do with a very worn out engine, is that right? If so, the dealer is trying to avoid their legal obligations. It has not used oil since, but uses more fuel and feels sluggish compared to before. Should I just have it changed? Forget the a-hole dealer perhaps. This is my first Hybrid. I don't know where to start. Sorry nearly forgot, I'm in Phoenix. Any good mechanics that you could recommend? Just so I don't end up in a liable case, I did not buy it from a Toyota dealer there. It was from a used car seller, non-franchise.

 

Yikes, I didn't think anywhere in the US even sold that grade engine oil any more. In Australia we still get quite a few people using really thick stuff like that, not that I'd recommend it.

Yeah, change the oil to the recommended grade and monitor the oil consumption. Be careful not to let it get too low before topping off.

Re my previous question. What was the oil consumption rate before they changed to the extreme viscosity oil? I mean, was it like a quart every 2000 miles, was it a quart every 500 miles, what was it?

 

my wife was driving and a light came on. she went to the nearest garage and they put oil in it, not being there,

i can't be sure but she thinks maybe, couple of quarts. I don't know what the level was 2 weeks prior bcause the dealer said it was all checked out and fine, so I must admit
i never checked it when
i picked it up.

with the fresh mornings
i have noticed it runs like a dog first up since the thick oil went in.

We have only put 670 miles on it.
i think I might have a lemon!

 

Ok, well that's the first thing you need to do then. You need to properly quantify the amount that it's using with the correct viscosity grade. Get that rubbish that the dealer put in drained out as soon as possible, before it damages the engine further.

 

Thanks for your time and effort uart.
i'll do just that and post any further developments. Although there are other problems with it too. That's why I suspect I bought something that has been belted by the original owner!!n Steers like a dog too, but thats on another post.

 

I've heard of high mileage gen 2's using a lot of oil from several people. They have really bad cylinder taper at high miles ( according to one Toyota dealer tech)
The good news is that used motors are really cheap for gen 2. You could probably have a used motor installed for $2000 and you will be back in action. I also heard that when the gen 2 prius motor finally lets go it throws a rod through the side of the block.