High Oil Consumption

I'm inquiring at what point I should be concerned with oil consumption on third generation 2010 Prius bought new and serviced regularly by dealership. It beeps at 2 mm on stick and rounding curve at 40+ mph, but does not signal with low oil pressure until off stick with rounding curve at 40+ mph. It started this just after 60K oil change (end of warranty), and now has 73K; early in my books for high oil consumption. The service manager at dealership was so baffled he agreed to comp the 70K oil change as we all thought maybe insufficient oil was initially replaced. Unfortunately I live in a town with relatively few hybrids, so am not comfortable with even dealers (two within 30 mi) service. It does not leave any marks in driveway, as it appears to consume only when gas engine engaged, so need to check after any extensive highway driving, etc. Any input appreciated,

 

Did you read the entire thread? I provided my input a few times how piston soaks/oil flushes do wonders on toyota engines with stuck oil rings. How much clearer could I be?

 

In referance to your oil consumption from my experience on this issue & reading these web sights my sugestion is that you check your EGR valve. On the EGR valve there is a tube that is about 10 t0 12 inches long that can get plug up with carbon from the exhaust. It that gets plug up chances are your PCV valve will also get plugged up. One or both of those will lead to excessive oil consuption. Hope this will work for you........................ George

 

would you have mechanic at dealership perform this maintenance or nondealership mechanic?? Not even sure any nondealership mechanics here would take this on.

 

You are more likely to find a non-dealership mechanic to do it.

 

It's still beyond me as to how an engine would develop stuck oil-control rings if it has been using a top-quality synthetic oil at the proper intervals, especially after only 70k.

 

The so called "top-quality synthetic oils" are usually formulated with group III base fluids (mixed with other things of course).

The problem is when oils were formulated with group II+ base fluids (sometimes around 2000), solvency dropped rapidly and oils were not capable to deal well with high temps deposits, something that group I oils solved easily.

You should remember the Russian 400C oil test posted on BITOG some time ago. The most expensive oils gave the worst high temps deposits and the cheapest diesel oils did the best.

 

But ruizfamily-u2c3 has a 2010 which surely has used API service SM or SN oil exclusively.

It's possible that they ran low on oil near the end of a 10K mile oil change interval (by not checking the oil level) and then had the problem with increased consumption due to oil lacquer build up on the OCRs. That is the owner's fault, not the type of engine oil used - dino or syn.

They could have a lemon, too. Even Toyota makes them.

 

so what's your suggestion?? the dealership had it for two days at 67K with audible alert for me (first time it ever alerted), but could not duplicate despite thorough description of driving conditions. They returned it to me and said bring it back if shows low in 600 mi, which it didn't (but it does not get a lot of driving at gas engine speeds). That's why they considered that their oil man may not have put enough oil in at last change and comp'd the 70K oil change.

 

It's still your responsibility as the owner to periodically check the oil level. I rarely allow another mechanic to touch my car. Oil changes? Who do I trust? Me. (As Tony Montana states in Scarface). I check the oil level in my cars every two weeks.

You should always verify that the grease monkey who changed the oil in your car the last time didn't underfill or overfill it. Each instance is bad news.

What do you do now? Are you absolutely sure that your Prius has a high oil consumption problem? For a car as new as yours and only 73K miles, you should be consuming no more than a quart every 7000 to 10,000 miles. If your car is consuming 1 qt every 1000 miles, that's unacceptable and you should contact a Toyota zone manager. Trouble is you're way out of warranty and will need to depend on their good will if they determine you have a lemon.

friendly_jacek might be right that you need to get the oil rings loosened. But these procedures are risky - piston soaks and oil flushes, if done improperly, can damage the wide band oxygen sensor and catalytic converter, and -heaven forbid - scuff a piston or cylinder bore. Not worth the risk IMHO.

 

spoke with customer care Toyota corporate office, then took car to dealership on outskirts to initiate oil consumption test, they found and repaired oil pan seal leak as goodwill repair. Now off to drive mi and have it checked for any additional consumption. Thanks to all who replied.

 

Hopefully that is the solution

 

An oil pan gasket leak, huh. Those are rare. Hopefully that was the only
abnormal problem with the car.

 

still consumed 3 quarts in 600 miles, so going in for further diagnostics Monday; hoping they can discern why my prius consumes oil (of course only when gas engine engaged)

 

Wow, that's a real bummer. Hopefully, Toyota will find the root cause and repair it for you gratis.

 

3 qts/ 600 miles ??? This is as bad as it gets.

Forget my previous comments about ring cleaning. Nothing will fix it short of ring replacement job.

 

Dealership, that resealed oil pan, sent me away to return in another 200 miles as still sitting on full after 357 of mixed miles; prior 600 was 90% highway so almost exclusively gas engine. Tried to explain that it does not consume when running on battery, most of intown driving. Oh well another hoop for corporate (any hope of having rings replaced by dealership/Toyota??),

 

You could ask them to test crankcase air pressure before the PCV valve. This would show if the crankcase is pressurizing. If the PCV valve is not keeping up with the CC vapors, there is either lots of blow-by, or a problem with the PCV valve/system.

A compression leak-down test would be the easiest way to determine if you have really bad rings and compression.
You may have to search a shop that does this sort of test. It is the main test used on piston aircraft.

Good luck and thanks for keeping PC informed!

 

And just to recap,,, You do know how to determine your own oil consumption rate, correct??

 

So take a 200 mile round trip on an interstate highway at 75 mph and return to the dealership to prove to them that the oil level dropped. Anyone you haven't seen in a while that you could visit on the 4th and after? Take a couple of quarts of oil with you just in case the oil pressure light comes on.