2010 Prius 9k Oil Change 2.9qt Consumption

Hi guys,

The Prius has been consuming oil since I bought it at 94000 miles. Not a big deal its not a terminal problem. I do all of my own maintenance and keep up with everything. Just rolled up to 172,000 miles. Changed the oil and 2.1 quarts came out after originally putting in 5 quarts of 0w-20 Full Syn. After seeing this I thought wow lets see what the intake looks like. Air filter is still sparkly clean, top side of throttle body is sparkly clean, opened throttle body and it was oily. Went to go get a big screw driver to hold it open and I dipped the screw driver into oil. There was a couple ounces of oil in the intake. Took the intake off and inspected all of the hoses and the pcv hose was the only hose with oil residue in it besides all of the carbon/oil residue in the intake manifold. Replaced the PCV valve but I shook it and it sounded the same as the new PCV. Went ahead and threw in a bottle of Engine Restore as I've seen good results before. Put 5 quarts total back in between all fluids. I'm going to keep an eye on it and see how it does over this oil change. Anything I might also need to check? The car runs fantastic and I have had no issues with anything else. I'm not even sure the cel works as I've never had it come on (kidding it does come on with the ignition cycle so it does work).

I'm assuming if the oil consumption continues I will try the old Turbo Volvo OEM PCV Valve catch can that drains the oil back to the sump instead of keeping it in a can and see if this decreases oil consumption.

 

Yeah I over fill by 0.6qt. Makes life easier and I figure since we do it in our race cars by adding another 1/2 quart to keep oil in the wet sump near the pick up tube for oiling in the higher G turning applications it will be okay.

 

I have had a wide range of cars in various states of condition. I had a 96 civic that consumed a quart every 280 miles. It ran with no check engine light, but I just had to put oil in at every fill up. I bought it with 150,000 and rolled it up to 185,000 over one summer and sold it to the next guy for $500 more lol. So you can do a lot with a little.
I always check the dipstick on the Prius and I don't worry about it until the oil level goes off the dip stick. It's not a great way to do it but you would be surprised what amount of oil range a car can accept. For the most part as long as you follow the oil intervals and don't run the sump out of oil below the pick up the they will tolerate having only very small amounts of oil. A couple of the guys I know in Texas will go ahead and put in an extra quart or TWO of oil in the hot LS corvette Camaro etc road course cars because it keeps the oil in the sump on the higher G autocross or road course stuff. Common knowledge and has helped with motor longevity on a lot of wet sump cars with high G applications. Also this is in the LS motor where you will get windage losses from the cam sitting in the oil at a certain point. But yeah they did this on engines with known pcv and ring problems lol

Alright we are now 1100 miles into this oil change. Can't see much. Oil level hasn't dropped but we will see. I don't think it will fix the issue but I would like to try and go in order on things and see if they work.

I'm betting the rings and pcv won't be the issue. I'm guessing it will be valve seals. But as of now I do not know until we get there.

To the guy who said something about the catch can routed back to the oil pan. It's not a big deal. Volvo used it with great success. It becomes a wear item like the egr as well and will need to be cleaned (or replaced since they are so cheap) every once in a while. It's more of a carbon build up problem with these similar to the egr/pcv system.

 

Also yes condensation is a non issue. It's a daily driver everyday typically 25,000 miles a year. The oil gets hot enough on the commute that it burns off the water vapor with the help of the cv system.

I'm with you on that. I may swap to 0w-40 after.

 

I will say that all cars DO in fact consume oil. Just because your oil light didn't come on or it stayed on the stick doesn't mean it consumed zero. Generally most people won't notice because their oil intervals are not long enough to notice. Next time you change your oil drain the oil back into the 5 quart bottle. I bet you will be down about 3/4 of a quart in that time. I do this every time I change my oil hence the reason why I add the whole 5 quart bottle. But with that said I have had cars that with have more oil in bottle after doing the change. Gasoline dilution into the oil can increase the amount of fluid in the oil change going back into the bottle. Lol

 

If the Volvo part works I'll add a snarky title like "The $26 Volvo Part That Toyota Doesn't Want You To Know About."

It may not work but I just checked the throttle body and I see oil in there again. Hmm... I'll log back on in 4 months and let yall know what's up.

 

True that. I just prefer maintenance free items. That's the toughest pcv to get to I've ever seen lol

 

More or less I don't see people wanting to climb in and empty that little can back into their engine every 500 miles or whatever to "solve" their oil consumption issues.

 

Update: 3k miles and we are at 1 quart oil consumption like normal. Engine Restorer had no effect. Now to drill a hole in the oil pan and install the Volvo catch can.