My Toyolla is Consuming an Alarming Amount of Oil

I replaced the generic Autozone PCV valve with the OEM Toyota one.

It is at this point I would like to note that the mechanicals of the two valves are completely different. The old valve required a pair of channel lock pliers to pry free of the valve cover. It and the vacuum line leading to the intake manifold were both filled with oil. In contrast to the crappy Autozone part, the Toyota valve snapped in to the valve cover like a LEGO brick. I also replaced the aging factory pinch clamp with a brand-new worm gear clamp just to be on the safe side.

The engine has been running rough for a while, which I attributed to the motor's age, the "Polar Vortex," fibromyalgia, and/or poor astronomical alignment. Well, that stopped immediately. The engine fired up on fewer cranks and idled smoothly even though it's almost as cold outside as my ex-wife's soul. (It normally has to warm up for at least 5 minutes to idle smoothly.) While the engine was idling, I removed the oil cap, which proceeded to get sucked back into the fill hole by a healthy dose of crankcase vacuum. I believe that not only was the previous PCV valve functioning incorrectly, it was also creating a vacuum leak, something that speed density EMSes generally don't like.

I also topped off the oil and noted the mileage. We'll see how the oil consumption is now.

TL;DR: Old PCV valve bad and filled with oil. New PCV valve makes car run better.

Nice. Sounds like a win.

I believe most PVC valves causing oil consumtion is caused by sludge or carbon filling up the oil seperation baffels in the valve cover. A PVC valves funtion is to shut off when vacume stops preventing crankcase smoke from getting into the intake manifold while the engine is off. This smoke must produce varnish or such other wise I wouldn't know why it is so bad.

My DD a 3.8 Mustang has a defective valve cover that lets oil into the PVC. It has been getting worse, and the fuel fiklter in the line no longer worked. I had to build an oil seperator from and old glass fuel filter and I get a lot of oil in it. My oil buring was only 1 quart in 5 thousand miles.

For oil burning from carbonized valves I used to try the MMO piston soak on a Saturn. It didn't seem to help but thicker oil helped a lot.

I thought for sure my 230k+ mile 1MZ in the MR2 was dead. (Not that hard, given the general consensus around here.) It smoked on start-up about every 5th trip. One day on the way to haul my kiddo to school, it went into crop-duster mode and I didn't think I would make it home.

Turns out the PCV valve was dead. It was on my list...I could have sworn I changed it. Long story short, it was gulping massive amounts of oil into the intake. Since then, never smoke, no more oil consumption. Still runs like a new engine and survived about 1500 HPDE miles this summer.

My dad's Chrysler minivan started burning a couple of quarts between oil changes -- also a dead PCV valve.

Had a buddy who killed a turbo in his WRX. Inside were the remains of the guts of the PCV valve.

TL;DR - PCV valves are the first place I look when oil consumption increases suddenly.

1MZs are notorious for turning into oil processing machines.

Seafoam is on sale at Pep Boys, 2 for $13. So I dumped 4oz in the crankcase and the remaining 12oz of the can into a full gas tank. I'm going to change the oil in a few hundred miles and then see how the oil consumption goes. And I still have another full can of Seafoam if I want to kill all the mosquitoes within a 3-mile radius of my house.

In case anyone was wondering what the Toyolla looks like:

Update, for anyone interested. I changed the oil last weekend and drove about 500 miles to NC for a business trip. The oil level is unchanged, so I think the PCV valve was definitely at least a large part of the problem.

I am jealous of the Toyolla. I lust after an AE101 wagon something fierce.

mndsm wrote: I am jealous of the Toyolla. I lust after an AE101 wagon something fierce.

Not gonna lie. I freakin' love this little car. I just helped my girlfriend move, and we didn't even need to rent a truck. The Little Toyolla That Could moved it all in three trips.

I kind of wish it were in a bit better shape and had far fewer than 190K on the odo, because I'd love to clean it up and slap a new coat of paint and some nicer wheels on it.

My first car was a sub-rental level sedan of that marque- I beat the hell out of it and it kept going. I have a 99 now (AE103, with the 1zz instead of the 4afe or whatever it was in the 101) and I'd trade it in a SECOND for an AE101 wagon. Very few cars get me like that one does.

If you keep the Corolla for a while longer, just do it. Especially with the paint, it will help keep the body in good shape.