Oil consumption...what I did to correct it.

Do you think the previous owner just ran regular oil changes and didn't used synthetic.
I suspect the oil lands build up is due to regular oil changes and these cheap oil from Jiffy lube doesn't last as long and doesn't have any oil detergent to keep clean on higher mileage Prius or just gas engine cars. I wrote a thread and suggested seafoam treatment or engine oil cleaning for every other oil change on high mileage Prius over 100k. I feel 2nd Gen Prius could greatly benefit from this type of cleaning service interval. What's opinion on this matter? I also installed a oil catch can and it gets 5 oz filled every oil change. I feel this keep the oil from burning in the Catalytic converter and keeps the Prius cleaner burning car. Love to hear your opinion.

SM-J737T1 ?

 

I wanted to try what the OP did but im hesitant. so i have been using BG EPF instead the last 3 oil changes. the oil is real dark everytime i drain. i also add half a quart of oil to wash most of the old oil out from the pan. After refilling, the oil is so clean its hard to tell where the oil line is on the dipstick. i'll probably continually be using the EPF every oil change to unclog those oil holes each OC. if i see no more improvement, i'll do every other OC.

i also have a mini catch can installed. milky stuff when its humid out. oily when not. about half a fl oz a wk. (newish PCV valve)
Previous 2 OC, i didnt realize i had a vacuum leak with the catch can. but i have since sealed it up. that helped improve the oil consumption on this 3rd round. its not dropping as fast as it used to. right now its a qt every 2000mi or so. before it was almost a qt every 1000.

Also, last 2 oil changes i was also using 5w-30 penzoil platinum. then 5w-30 m1. this time i used 0w-30 M1. 5000mi OC.
its just coming up to 3k at the moment...

eventually, i'll probably change the rings for a more permanent fix. or upgrade to a 3rd gen and maybe change its oil rings.

 

We have a 2005 Prius with 246K miles. It has consumed excessive oil since we have owned it but only on freeway trips..
If driven at low speed in town it's consumption drops considerably.
I have tried oil flushes, synthetic oils etc.

We recently replaced the catalytic converters because of the P0430 catalyst efficiency error.
Coincidentally we put Mobil 1 high mileage synthetic in it.
The consumption has dropped dramatically from about 1 quart per two weeks of driving to less than 1/2 quart every 2 weeks.
My theory is that all that previous oil consumption contaminated the cats and partially clogged them causing excessive back pressure. This may cause excessive exhaust pressures and oil blow-by? The power also increased after the cat change.

As an aside I have put my engine scanner on it while driving and watched the engine coolant temperature.
In the winter it rarely ever reaches thermostat activation temperature. This would indicate that the oil temperature probably never gets to operating temperature as the engine is turning off and on as needed. This may cause sludge build-up on the piston rings.

I think engine flush just before an oil change might be mandatory in these cars.

 

Sparkey, 2 weeks equals how many miles??

 

Just wanted to add an update to what i considered a permanent fix.

by Dec 2020 i decided i've had enough of worrying about the oil levels so i tried what Danlatu was saying is his fix. changing the piston rings to aftermarket. I have a 2008, & 2011.

I did the 2011 first, changed all 3 rings in 4 pistons. so far it hasnt been consuming oil in 20k mi.
it was easy to do. the engine looks like new. since i had the tools i decided to upgrade my 2008 and bought a 2012.

2nd up was 2012. since i bought a non running ex uber car. this one i only decided to try just changing the oil rings but not the 1st and 2nd rings. its slowly started consuming oil and by 10k Mi is now at same level consumption like before. conclusion. best to change all the rings at once.

3rd was the 2008. my son wanted it for himself. so i also changed all the rings with aftermarket and made the oil ring holes just a tad bigger. so far it only has been 10k mi. but oil consumption has stopped for it also. the most time consuming part was the valve adjustment. 3rd gen had hydraulics so i didnt even have to mess with it and was faster to do.

Since i did all the work myself. no machine shop was needed. i did everything old manual method. I spent approx $1000 per engine in parts. i bought flexhones for each gen also. and the 3rd gens i upgraded a few parts so they cost just a bit more. so far they all are running great!

i will probably have to redo my 2012 piston rings at some point.

 

Can you elaborate on the following?

"the 3rd gens i upgraded a few parts..."

Posted via the PriusChat mobile app.

 

I've thought: you could replace the stock rings with fresh Toyota rings (the original, low-tension style), leave the pistons as-is, except to drill out the oil passages slightly, and be good for at least another 100K miles, likely more. Especially if you went to 6 mo or 5K mile oil interval.

 

It is the top ring and second ring rolling causing the oil use problem because the ring is no longer working as an oil scrapper. There are after market rings called gapless rings, the second ring has a groove machined into the lower edge to contaminate an oil ring rail. The ring ends are offset so the gap is sealed in the second ring and the oil ring rail won't roll and continues to act as an oil scrapper. The low tension ring design remains but any blow by from the combustion or oil into the combustion chamber is eliminated.
Not selecting the braking regen while in the "running in" phase and being gently on the throttle so the engine doesn't spin up hard will also help.
Avoid friction modified oils or any oil additive for the first 10,000km after a re-ring to allow the rings to wear to the correct shape.

T1 Terry

 

FWIW the oil in my daughter's 2007 with 295,000 miles on it always looks fresh on the dipstick. Looks just like it does after an oil change. In all my years I've never seen that. The dipstick oil is always black a few days after an oil change. Full disclosure, this engine did get put in at 220,000 miles and had 40,000 on it. Original owner hit an oil consumption problem and down went the original engine. We use full syn on this sucker.

 

It would be interesting to see under the tappet cover to see if it is built up with sludge. Many full synthetic oils do not have a detergent package as they were designed for high performance race engines. The detergent makes the oil froth and can cause aeration in the oil leading to cavitation of the pump and good bye a set of bearings.
The race engines a stripped down regularly, so no issue with sludge build up and they always operate at full engine temp, so no water condensation in the oil either .....
Passenger cars on the other hand rarely maintain full operating temperatures for very long, ones that run intermittently like a Prius engine, spend most of their time below operating temp. and returning to operating temp.
This causes the water boiled off out of the oil ends up in the tappet cover, the detergent in the oil washes this off and holds it in the oil ready to be removed when passing through the filter or when the oil is changed.
Basically, black oil is doing its job, oil that doesn't go black or change colour close to the end of the oil change period, is not doing its cleaning job. The end result is all the sludge ends up in the sump eventually, fills up till it blocks the oil pick up and that is the end of the motor due to oil starvation ........

T1 Terry

 

were you burning oil? Have you seen an improvement using BG?

 

I was going to try the BG products, but decided on the cheaper $10 and more available Motor Medic Motor Flush. I don't have enough miles yet to know if it helped oil consumption, but it cleaned all of the staining off of the dipstick and oil was very black, and the new full synthetic 5w-30 is very clean so far and holding level. I think I may try it again on the next change and note any color improvement. I didn't want to try the ring soak unless it was a last resort, and I think it makes sense to focus on the bottom end first where the oil ring is closer to by using oil flushes. Here is a thread on MMMF flush: IT CLEANS--- Motor Medic Motor Flush | Page 3 | PriusChat

 

You will definitely have to do this more than once. It would help also to do 3 or 4 short interval changes at 2,000 or 3,000 mi intervals as well to get the best bang for your buck and see results quicker.

 

Sorry Folks, was away for the weekend Boy Scout Rock ClimbingTrip.

I replaced the VVT cam adjuster with the latest version so it doesnt start with a rattle. i hated hearing the creak and groan of the head bolts during tighttening so i splurged on ARPs. i intend to keep the prius as long as i can keep them alive. and i swapped the oil filter to canister. but now i wonder if it has a oil pressure valve or not. havent researched that yet.

 

Hi Mendel,
i believe you can but i think over time it will just have the same situation as before. i rather not do it again if possible.
so far my MPG is between 43 ( i bring the kids to school and go home where the engine doesnt even warm past 60 C according to my app.) and 47 when i do lots of long travel. so standard rings works fine for me. i use M1 0W-30 at the moment. this car has 356K mi now.

 

for my wifes 3rd gen, i had her use 5w-30 i think for the first 5k mi. now on 0W-20. i really hope it lasts at least 100k mi. she is at 20k now. i do all the maintenance now...

 

Most likely i was. its just gone with no idea where it went. not a drop anywhere.
i tried BG EPR, MOA, even seafoam, motor flush, concoction etc. even different oil brands. M1, Pennzoil, nothing really helped permanently.
with BG it seems to help for the first 2k mi. but thats it.
The only thing i havent tried is thicker oil but i had a previous bad experience with that so i didnt want to even try.

I am glad i made the repair. now when i do oil change its just like the old days. oil & filter, done.
no need to spend extra on cleaners modifiers etc. also the worry, specially on the cars i dont drive. my family does not even check their oil nor tire pressure.

 

Our '08 "Taxi Prius" now has over 730,000km at least on the clock (approx 460,000 mile) (the dash goes blank on a regular basis now and the odometer doesn't add anything to the total when it's off) It uses maybe 1 ltr (2 pints) between 10,000km services if she drives it hard on the regen on the steep part going into Adelaide, other times it doesn't use any ....... so running in correctly is important, using a detergent oil and regular oil changes is very important.

T1 Terry