Low oil - Red Triangle w/ Exclamation Point

Have you checked or replaced the PCV valve a common cause of oil consumption.

 

good idea. The PCV is not easily accessible so I traced the hose to the intake manifold, disconnect, and blow in/out. I can definite hear the clicking of the PCV back on the valve cover. The flow is blocked one-way, can't blow back toward the valve cover (correctly).

so i think the PCV is ok. Though I did notice the inside of the black hose is wet with oil, but not excessively. So there is definite oil flow but can't tell how much.

 

I believe it is recommended to change the PCV valve at 120,000miles, it is an easy job and not an expensive item to purchase. Well worth the satisfaction of knowing weather it is causing the problem or not.

 

I think there's a difference between the British model and the US model in terms of the accessibility of the PCV valve.

I've seen some write-up here of guides to changing the PCV valve and it looks like quite a pain. Wipers and a bunch other stuff need to be removed.

When I looked at my Prius however (Australian model) the PVC valve is totally accessible, I'm certain I could get a spanner straight on it without removing a single thing! I've heard the British model is the same.

I haven't totally figured out why the difference, but it definitely seems to be related to some extra "plumbing" that the US models have up around that area.

 

You don't have to remove the cowl + wipers, but, after removing the intake and unbolting the main engine wiring harness, clearance is tight, about 2-3 clicks on the GearWrench. There is no clearance for a ratchet due to the IC pump reservoir. Use only a box wrench, not an open-end, and definitely not a Crescent wrench.

uart, is your car right hand drive? Do you have any pics posted of your engine bay?

 

Yep we're right hand drive here, same as the Brits.

The area around the PCV valve is quite different to what I've seen of the US model. I'll take a picture later and post it.

 

That does not mean the value is good. PCV valves don't last forever and when they go bad it's because they don't seal right, not because the spring breaks and causes the one wayness to fail. It could and probably is letting oil by.

 

I never quite understood how a PCValve stops oil. It is really a simple device, basically a spring load one-way valve; mainly to prevent flow going back in to the crankcase. During high crankcase pressure & high input vacuum, it is basically open all the time. So there is always oil mist in the blow by gas. It is a problem if it's stuck open and thus always sucking. An improvement would be a catch can to collect the heavier oil while still letting the gas blow by.

All the auto manual i've never read tells you to test for the rattling noise, indicating it is not stuck, and the one-way flow.

But it is cheap and I can certain change it; though I don't like changing thing un-necessarily

 

Ok it took me a while to get around to it but here are some pics of the PCV valve on the RHD Prius (Australia UK etc). There is nothing removed in these photos, just opened the hood and snapped them.

 

On the US model, that shiny bolt in the center of your pictures holds down the engine wiring harness, which makes a 90 degree turn over the top of the PCV and then runs over the top and parallel to the hose.

 

I'd say it is more likely that the switch to synthetic oil will accelerate the engine oil consumption.

I don't think it is necessary to change the oil every 3K miles given the rate at which that you are logging miles on the car, but it is necessary to check the oil level periodically and add oil as needed, to ensure the oil level doesn't ever drop below the lower dipstick dimple. If you are using a name brand synthetic oil then you should be able to go at least 7,500 miles between oil changes, which would imply that you would add at least two quarts of oil between changes.

 

This is cause by low coolant from the leaking water pump. You most likely do not need the control valve.

2500 miles per quart is not too shabby for an engine with that mileage, especially since you are the second owner. Since one of the main reasons to use synthetic is to increase the oil change interval, I'd suggest using something like Castrol High Mileage (conventional) or a cheaper synthetic blend, if you are changing every 3K.

 

I have to add a quart every 700 miles. once a week!

 

I also have to add a quart of oil every few hundred miles, basically once every two weeks.

Recently replaced spark plugs. All of the old spark plugs indicated potential valve guide seals leak resulting in seepage of oil into the combustion chambers. Do not know how difficult, and/or expansive, of a job to replace all of the seals.

 

Hmm, I am wondering how an examination of the old plugs would lead to the conclusion that the valve stem seals are leaking. Was a compression or leakdown test done on the engine?

If not, then the oil just as easily could have come from worn piston rings.

If in fact the valve stem seals need to be replaced, this would require removal of the engine head so that the camshafts can be removed and the valve stem seals replaced. Probably a high three-digit or low four-digit repair. Depending on your odometer reading it might be better just to have a used engine installed.

 

I just joined the high-oil-consumption club at 142,000 miles. Got the Red Triangle of Death now and then - a brief RToD with a beep, usually when coming to a stop. I was misled by some forum posts blaming this on the 12V battery, so I replaced it (it was over 5yo, so WTH). After doing that, while I was cleaning up, I checked the dipstick, and nada! Took over 2 qt (Mobil1 5W-30) to get into the normal zone. The last 7,000 miles or so included a 3500-mile cross-country trip from FL to WA, often at 75-80mph. I had always been impressed by the low oil consumption and hadn't bother checking it until it was changed. Needless to say, I'll check at fill-up time from now on.

What I don't understand, is why there were no diagnostic codes?

 

we applause your candidness. you don't get an oil light until it's too late, no idea why, probably just cost savings.

 

I've read there might be some high-end car brands with oil level detection, but I've never owned a vehicle that had anything besides an oil pressure warning. Of course the trouble with an oil pressure warning is the pressure is fine until the oil drops below the pump intake and then it isn't, at which point you're already eating your engine.

Regularly checking the dipstick is the one and only kind of oil-level warning I was ever taught to count on.

-Chap

 

The point of my question was that the only warning I got from the car (other than the dipstick, mea culpa) was the Red Triangle of Death, and after receiving that I hooked up the code reader and it said no codes. Seems like there ought to be a code for "low (or no) oil pressure".