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2003 Toyota Avalon smoking and misfire on cylinder 2

Hey guys. I need some help please. I just bought a used Toyota Avalon with 135,500 miles on it. They sold it because it was smoking and didn’t know what was wrong with it(they were an old retired couple). They were the only owners and it has never been driven hard or abused… Anyway. I read online that unhooking the vacuum hose from the pcv valve may make it stop smoking. I unhooked it and plugged the vacuum hose and they were right. It stopped smoking after I got the rest of the oil out of the hose. I thought maybe the old pcv valve was messed up so I got a new one and hooked it back up but then smoking was back. So I am getting too much blow by in it for sure. I don’t think the valve seals are leaking because as soon as I unhooked the vacuum from the pcv valve the smoking stopped. I drove it for 2 days with no smoke whatsoever. What could be causing the blow by to be so strong? It was strong enough to spit oil out of the pcv valve without the vacuum hose sucking it out(there was oil on the engine).

The check engine light is also on so I hooked it up to a computer at an auto parts store and it said I had a misfire on 2 cylinders(2 and 6). So I changed all the spark plugs and re-hooked it to the machine. This time I only got an error code for cylinder 2. Each plug has a coil so I switched the coil from cylinder 4 to cylinder 2 to test if maybe the coil was bad, but it still gave me a misfire on cylinder 2 only. I even swapped the plug from 2 to 4 to make sure the new plug wasn’t bad. Still a misfire on cylinder 2.

Any help would be much appreciated. It is still smoking(ONLY WHEN VACUUM HOSE IS ON PCV VALVE) and check engine light is still on and error code says cylinder 2 misfire. Thanks in advance for any answers!

You might want to do a leak-down test on number two cylinder.

If the leak-down test indicates a problem with the piston rings in number two cylinder, this will cause the crankcase pressure/heat to increase where the oil becomes volatile. Under this increased pressure and heat oil is forced thru the PCV system to be reburned in the engine. When the vacuum hose is disconnected from the PCV valve, you’ve cut off the oil supply to the engine to be reburned. But the oil still comes out of the PCV valve.


Thanks Tester. I am bringing it to the mechanic on Monday to have him look at it. I don’t know too much about cars. I am just now learning. How bad would it be if the piston rings in the number 2 cylinder were bad? How much do you think I would be looking at to get it fixed? It isn’t using much oil really, how bad would it be for me to run it with the pcv valve unhooked from the vacuum hose? I was thinking about running a hose from the pcv valve down below the engine to stop it from leaking on the engine and smelling like burnt oil all the time.

If any of the piston rings are bad you have three choices. Rebuild the engine you have, replace the engine with a used engine, or install a remanufactured engine. None of which are cheap.


Think it would be ok to just disconnect the vacuum hose from the pcv and plug it until I get the money to fix it properly?

If you plug the PCV system the engine crankcase isn’t able to vent. The pressure in the crankcase can build to a point where it can blow the main seals out of the engine. Not a good idea unless you plan on replacing the engine anyway.


I don’t plan on plugging the PCV valve, just the vacuum hose. I would run a hose from the pcv valve to below the engine so any oil that blows out wouldn’t run onto the engine and burn.

No not plug up,that’s a bad idea. You crank case over pressurizeies and you blow every seal in the motor. but I guess technically you could undoo the hose and run it into a container to catch the oil. At least for a little while as you figure out what your doing. There always a small chance that the rings are just stuck and as you drive it they may come loose again but this is a very slight chance.

If you run a hose onto the engine where the oil can burn, you get SMOKE!

Besides, oil starts on fire faster than gasoline does when it hits a hot engine component. You want an engine fire?


I don’t want to run a hose onto the engine. I want to run a long hose down below my engine and behind it so any oil that blows out of the pcv would be on the ground not the engine.

You have to be kidding me?

Not only are you dumping used engine oil all over the roads, but I bet those people behind you appreciate the oil all over their windshields.

Your’re a nut case!


Gsragtop. I don’t plan on plugging the PCV valve. I want to remove the vacuum from the valve and put a long hose onto the pcv valve that will still let the pressure realease but it wont suck the oil blowing through it back into the engine that is causing it to smoke

Tester I was asking a question to get an idea if it was ok to do that or not. I don’t need you to insult me. It is barely burning oil(much less than a quart per 3000 miles so it’s not like it is “dumping” all over anyone or the road). Don’t answer my posts if you are going to be a douche bag about it.

Anyone ever use Auto-rx? Do you think it is safe to use or could possibly help get the rings to seal again if that is even the issue?

Tester’s right. You’re nuts. It was an observation, not an insult. And frankly - after all of the help he gave you to call him what you did? You sir, are unworthy of assistance. And just when I was I was going to offer some too.

lol. Get outta here. I was simply asking a question. I didn’t need an insult. I am no mechanic nor am I too familiar with engines. Just trying to figure out how to fix my car. And just like he and you observe that I’m nuts. I observe that you are both douches but that’s just an observation not an insult… Give me a break.

Hey! Do a leak-down test on number two cylinder and it will tell the story.

You don’t have a thick enough skin to work or talk in an auto repair shop.


Lol. You are probably right. I do need to work on taking insults better. Definitely will ask the mechanic to do the leak-down test on the 2 cylinder, and I really do appreciate the info.

I am also wondering why the smoking isn’t consistent. Just went out and started the car and it didn’t smoke at all. Sometimes I will start it and it will smoke like crazy then other times it wont smoke at all on start up. Same thing with driving, it will smoke sometimes and other times not at all.

That could be due to a problem in the valve seal area; either faulty valve seals and/or oil pooling around the valve guide bosses. This can allow hot oil to seep past the seals and down into the intake ports. This creates smoke upon startup and yes, it can vary.

Really, you should follow the advice about checking the compression. Otherwise you will just be beating your head on the wall and possibly causing the car to go up in flames.

It could be that the elderly couple who owned the car did not follow a good enough oil change regimen and there’s a problem with oil sludged or coked piston rings and so on. It’s best to find out from the get-go what you’re dealing with so do the compression test and go from there.
An engine in good shape should be spitting out 180-190 PSI on all cylinders.