Gen II Burning Oil?

I think this is the one we're currently discussing. Less than 2 qts per oil change (5000 miles?) is not optimal but it's still fairly manageable IMHO. I don't think I'd be looking to change out the engine quite yet.

That level of oil consumption wouldn't normally result in noticeable smoking and really mightn't give any other significant problems either. Still it would be nice to know where the oil was going though, as in past the rings or valve guides or intake or whatever.

Different brand oils can have somewhat different high temp viscosity and different film strength and different volatility etc. So though it might vary depending on the source of the loss, choice of oil can certainly have some impact on the consumption.

Having personally owned the oil burner or two in the past, my advice to gdfrsn would be to just buy nice big 5+ qt jugs (this is what they market 5L jugs as in the US I think), fill about 3.6 qt at oil change and use the remainder to top up at somewhere about 1/3 and 2/3 oil change (2000, 3500 miles).

Also look on the bright side of having a "mild" oil burner,

1. You're always getting good upper cylinder lubrication and

2. You're frequently getting your oil additives replenished.

 

Yes, it's not being overfilled. I add 3.5 qts. when doing an oil change. But you bring up a good point. On aircraft engines it is common to underfill when doing an oil change because the final quart or two readily burns off or goes out the breather. Any chance that sort of thing happens on the Prius?

When I first noted oil in the intake manifold it was during an oil change. I thought that maybe I was filling oil into the engine too fast and the oil was going down the vent line(s) to the intake because the oil wasn't draining down from the cylinder head fast enough. But now I find oil in the intake even when I haven't just changed the oil.

I'll post an update after five fill-ups with Techroline. If that doesn't work I'll try cleaning or replacing the oil control rings. I haven't begun to research doing that. Is it possible to do with the engine in situ by just removing the oil pan? The Bentley manual I have doesn't get into the guts of the engine. Any recommendations on a manual that would cover this? Thanks for all the advice. It's much appreciated.

 

techinfo.toyota.com which is a subscription website.

Regarding engine disassembly, the manual suggests removing the engine and transaxle, then separating the two prior to disassembling the engine.

 

My 05 has 202,000. Burns about 1 qt every 1500 miles. Never any smoke or drips anywhere. I just keep up with it. I'm sure at some point I wont pass emission testing becuase the cat will get fouled up. Still cheaper than an engine rebuild or swap. Stil avg 52 in summer and 46ish in the winter. I'm good with that.

 

It is possible that there is something clogged in the crankcase ventilation system that is allowing oil droplets to be sucked into the intake manifold. I don't know the details of this engine, but on some engines this kind of sudden consumption can be traced to a clogged oil trap. You need a tech with lots of experience on this specific engine.

 

I have the same problem. It started needing a little oil at 3-4k miles between oil changes. I change my oil every 5,000 miles and was surprised at the fairly sudden oil consumption. I have 165,000 miles on an 06 and it runs strong. Adding a little oil is a lot cheaper than than a rebuild.

 

I have driven 122,000 miles on a 2006 Prius. I've changed the oil and filter every 5K miles. I've noticed less oil out (drained from engine) than I've put in (b/t 3.5-4 qts) since I bought the car new. I'd say roughly 1 qt less when the car was new. Now, after 4K miles, the oil level was at the bottom mark on the dip stick. I added a qt, drove another 800 miles and at the 5K oil change, it looked like 2 qt's drained from the car. The oil looks dirty but doesn't smell burnt. No bluish smoke from the exhaust that I can tell.

I had 189,000 on a 1991 Toyota Corolla. It didn't burn a noticeable amount of oil.

I don't think these observed drops in oil is normal for a car today. Possible reasons are leakage from the oil pan screw (but no oil where I park the car). Its unusual for valves to have incomplete seals in a new car. I suspect the rings didn't seat. This seems like a Toyota QA problem (now a cost and time problem for me and environmental issue).

 

I suspect a lot of the consumption problems have a few factors. Probably, exhaust valve seals lead to the initial problem, because there is no noticeable smoke. Oil gets sucked past worn exhaust seals due to Venturi effect, then gets vaporized in the cat. But then, oil consumption tends to accelerate greatly after the first indication of low oil, esp. the low oil warning light, which implies that there is now ring sludge/wear+cylinder wall damage, and the oil is much dirtier than it used to be. I have a dead motor sitting on a shelf with a blown main bearing that is awaiting teardown/autopsy, so hopefully I can refine (or discard, lol) the theory.

Strange how people forget that the average motor used to last less than 100,000 miles.

 

My 2000-2002 GM trucks used a ton of oil and so does our 2006 Rav4. My Prius at 155,000 uses about 1qt per 7k miles or more (much less than the GMs or the Rav4).

 

Running the engine on two quarts of dirty oil will reduce it's life. What's the surprise here?

Instead of just noticing that less oil was draining out you should have been checking the dipstick regularly and topping off when needed. The engine would probably now be in better shape if you had.

 

I've read all of the post here and would like to share my experience. I drive about 4K miles a month in my '06 Prius. I purchased it used in '11 with about 47K miles on it (if I recall correctly). I now have about 160K miles on it and I began changing the oil myself at around 95K miles using Mobil 1 full synthetic at 3K mile intervals. I was recently convinced that I don't need to change it but every 5-6k miles due to the long distance freeway driving I do (90 miles one way, 180 miles round trip daily, 5 days a wk). So I began changing it every 6K miles at 148K miles, and the last oil change I did was at 154K miles. I am about 4,800 miles into my next oil change, and just a day ago I was greeted by a quick flashing red triangle, with exclamation point in the center of it. On my audio/climate display area, it also flashed "Problem(s)". As I investigated, online, I was lead to check my engine oil. When I checked my dipstick there was some dirty oil at the very tip of it, I was shocked that there wasn't more oil in it. I triple checked it and sure enough there was almost no oil in my engine. I checked for leaks, puddles, anything to indicate leaking. No dice. After further research I reaIized that it's probably my engine just consuming/burning it. So I realized it's burning oil at about a rate of 0.80 qrts/1000 miles. As much as I drive, I'm concerned. I'm no mechanic but the advice I've received is that a partial engine rebuild would be the only real fix to prevent so much oil from being burned. So I've started looking for a new car. A few things should be noted about my particular vehicle. I moved to an altitude of about 6K' elevation at around 95K miles. I lived there for about 15-20K miles at which time I noticed a significant change in my MPG's. Dropped to about 42MPG. I lived where it snowed and drove into the desert for work. So I dealt with extreme temperatures since I owned it but went from freezing to hot during those 15-20K miles. After reading the owner's manual I realized that extreme temperatures and sandy environments will significantly impact the hybrid battery and mpgs. Since then I haven't been able to get better than 40 mpgs. And I avg about 36. Not bad all things considered but I'm pretty sure my hybrid battery isn't operating to it's potential, if much at all. I rarely hear my engine shut off as it used to when it used to kick into battery mode. Hope that helps any of you. Please let me know if any of you have any suggestions. Thank you.

 

DrivesALot, this is good info, i.e. Mobil 1 is not likely to prevent the development of consumption. I have wondered if those of us who do a lot of up and down are more susceptible to getting gas in the oil, which might cause bearing wear (I've never done an oil analysis). That said, your case is definitely a reminder to everyone to check the oil with every fill up or at the very least every 1000 miles.

As far as MPG, it is not altitude per se. I live at 7,000 ft and get 48-52 mpg. But if you are having to brake a lot on your way down, such that the hybrid battery is full early and a lot of friction braking is used, then MPG will suffer. MPG may also suffer if the cat is starting to get clogged.

 

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

Update: After changing back to 15w-30 penzoil motor oil my Prius is still using oil. About two quarts in the last 3000 miles at last check. I am thinking about taking it to the dealer and let them have a look under the hood. Or just keep adding oil and keeping a close check on the oil level.

 

There are A LOT of "Prii Burning Oil" threads out there. The one I keep an eye on and post to most regularly is this one:

http://priuschat.com/threads/2008-prius-burning-oil-at-135-000-miles.119318/

There seems to be a lot of good information on there and there really isn't a consensus as to what is causing or how to cure "oil burn" other than a salvaged engine. Some people have had success with Restore, Risoline, Sea Foam, high mileage oil, 10W-40 and some have had no changes with any of those. It can vary from Prii to Prii it seems.

My personal experience is 10W-40 has helped the most along with keeping the engine under 4,000 RPM's as much as possible. Ema still "burns" though but at 354K she's allowed, LOL.

Hope this helps.

Chris

 

There are A LOT of "Prii Burning Oil" threads out there. The one I keep an eye on and post to most regularly is this one:

http://priuschat.com/threads/2008-prius-burning-oil-at-135-000-miles.119318/

There seems to be a lot of good information on there and there really isn't a consensus as to what is causing or how to cure "oil burn" other than a salvaged engine. Some people have had success with Restore, Risoline, Sea Foam, high mileage oil, 10W-40 and some have had no changes with any of those. It can vary from Prii to Prii it seems.

My personal experience is 10W-40 has helped the most along with keeping the engine under 4,000 RPM's as much as possible. Ema still "burns" though but at 354K she's allowed, LOL.

Hope this helps.

Chris

 

This is exactly when I experienced my oil consumption. Any specific fixes if you have switched to synthetic oil and experience oil consumption? I have switched back to regular 15w-30 and so far the oil consumption continues. I have considered using Lucas oil stop leak to see if that helps.

 

Lots of oil loss Prius threads. Most have these few things in common:

Owner does not change oil themselves and or do not check the oil level at every fill up. Oil is never checked prior to change out to see if any progressive minor oil loss.

Owner takes his car to the dealer to have the oil changed. They use there "regular" oil which is vat dino. Dealer never checks oil and reports to owner hey your oil was low you need to watch it. They just pull the plug and then usually overfill it. Oil loss begins because of poor quality oil and or maintaining it low. Minor oil loss is never noticed between changes as no one checks the oil. But minor oil loss contributes to poor lubrication systematically and continues to exacerbate the issue. 50-70-90K miles later oil loss is now severe and for the first time the car runs so low on oil it throws a check engine light which alerts the owner to a problem. About 90% of Prius owners on this site as far as I can tell when seeing this cel never even open the hood to check oil or fluids. Car is taken to dealer,mechanic,jiffy and the oil now so low its throwing oil pressure light. Then it's omg how did this happen?

Btw, after a Prius goes through this really low oil loss incident it then begins to really eat oil. This event really damages the oil ring and scuffs the cylinders.

To further complicate the matter alot of people on this site over the years recommend to not run your oil to the full line to improve mpg's. That's ridiculous. This little motor needs every drop of oil it was designed for.

 

Ed you've nailed it right there.

 

I agree 100%!!! My consumption in 03 corolla started when, inspired by priuschat BTW, I left oil level in mid level between high and low. Normally, I always kept it at high and had no consumption. The idea was to see any MPG increase. There was no measurable MPG increase but oil consumption started at that very OCI. It took me some heroic actions to bring it under control. Ironically, I learned later that Toyota had TSB that modified dipstick for my corolla that increased oil capacity to prevent oil consumption in the first place.

I suspect that many other ideas propagated by PC (like radiator blocking) end up harming the engine.

 

Can we use 0W40. Anyone tried it yet?