has a pcv valve fixed anyone's oil burning issues?

[B6B]

after i installed my catless dp's i've been noticing and smelling blue smoke on decels when i come to a stop, nothing at start up warm or cold or that i notice while accelerating. im gonna try to pull the pcv valve later, i see that get thrown around the oil consumption/burning threads, just curious if a bad pcv ever fixed anyones issue, i'm preparing mentally for valve stem seals, just still hoping it could be something smaller. i m at 97k, my consumption is about 2 quarts every 4-5k. i primarily use pentosin 5w-40, sometimes top with another brand syn 5w-40 between changes. i aslo notice a slight ping, under a very light acceleration, which goes away under heavier throttle or idle. audible only at very light throttle under a minimal load (cruising basically) sounds like a lean or carbon build up type of ping, i did an intake treatment and it didnt change. that match anyone's pcv symptoms? curious that maybe a stuck open pcv might cause that? not sure how it works on our engines.

[ladiesgod]

Didn't do $h1T for mine!

[dparm]

For some, yes.

Blue smoke on deceleration is typically rings. Valve steam seals will cause the smoke at startup.

What do you mean you did an 'intake treatment'? Is your exhaust tip oily? How much smoke are we talking about, a slight puff, or is it a lot?

[Lor2435]

I thought my replacement had helped but it did not.

Honestly, 2 quarts per 4-5k isn't bad at all and well within factory specs.

[LJH]

almost 3 years ago my car went from using a half quart every 2500 miles to using a half quart every 12-1500 miles, it happened like someone threw a switch. I took the PCV valve off and cleaned it out with brake clean and re-installed....if I knew what a PIA it was to get off and on I would have bought a new one originally. Well anyhow, my car went back to its normal consumption and 25K miles later still uses a half quart every 2500 miles.

YMMV....

Cheers,
Jim

[Slow4]

Mine did not solve my oil burning issue; as of now, I've accessed that I have bad valve stem seals that will be replaced when I get my timing components and adjusters replaced.

I went from .5qt/1500 miles to 1qt/1000 to 1qt/700 within a three year time span.

[ladiesgod]

Mine did not solve my oil burning issue; as of now, I've accessed that I have bad valve stem seals that will be replaced when I get my timing components and adjusters replaced.

I went from .5qt/1500 miles to 1qt/1000 to 1qt/700 within a three year time span.

That's it???

ha ha ha.....I'm at 1qt every 250 miles!

[Slow4]

That's it???

ha ha ha.....I'm at 1qt every 250 miles!

Well, I mean if you want to throw in my timing issues related to guides and mechanical adjusters, and a slightly scored cylinder....then ya, burning a quart of oil every 500-700miles is not a big thing.

[B7S4ATX]

after i installed my catless dp's i've been noticing and smelling blue smoke on decels when i come to a stop, nothing at start up warm or cold or that i notice while accelerating. im gonna try to pull the pcv valve later, i see that get thrown around the oil consumption/burning threads, just curious if a bad pcv ever fixed anyones issue, i'm preparing mentally for valve stem seals, just still hoping it could be something smaller. i m at 97k, my consumption is about 2 quarts every 4-5k. i primarily use pentosin 5w-40, sometimes top with another brand syn 5w-40 between changes. i aslo notice a slight ping, under a very light acceleration, which goes away under heavier throttle or idle. audible only at very light throttle under a minimal load (cruising basically) sounds like a lean or carbon build up type of ping, i did an intake treatment and it didnt change. that match anyone's pcv symptoms? curious that maybe a stuck open pcv might cause that? not sure how it works on our engines.

I was burning through a quart of oil every 500-600 miles or so. I had leaky valve cover gaskets that were being replaced, so I had my PCV replaced at the same time just to cover both bases before I conceded more serious issues. (Note - I didn't have blue smoke or any other symptoms other than consistent and frequent oil loss). Fixed the problem - have hardly any oil issues anymore and when I check the dipstick, it is roughly where it ought to be each time. Hopefully there's some hope for you.

[dparm]

OP, is the rate of consumption increasing, or has it always used this much oil between changes?

If things are constant, I would just keep on driving it and not worry too much. If you get bored, you could do a compression test.

If it's drinking more oil each time you check, then I would devote some time and money into investigating why. Don't just start replacing parts at random.

[QIKRNU]

OP, is the rate of consumption increasing, or has it always used this much oil between changes?

If things are constant, I would just keep on driving it and not worry too much. If you get bored, you could do a compression test.

If it's drinking more oil each time you check, then I would devote some time and money into investigating why. Don't just start replacing parts at random.

For a BMW driver, you sure are smart. Thank you for sharing your expertise.

[RPMtech147]

For some, yes.

Blue smoke on deceleration is typically rings. Valve steam seals will cause the smoke at startup.

What do you mean you did an 'intake treatment'? Is your exhaust tip oily? How much smoke are we talking about, a slight puff, or is it a lot?

Let me correct you before we go and give a bunch of bad information. Blue smoke under LOAD is "USUALLY" worn rings/bores or both.bad PCV with give similar symtoms. Blue Smoke under hard DECELL usually means valve guides...and why is this? Because you have 8 sucker-******s making GOBS of negitive pressure and when that throttle plate snaps shut theyre goning to pull air from anywhere possible IE valve guides; Valve is open, pistons going down, negative pressure less then the pressure inside the Valve cover so some bad vavle seals with a sloppy guide is when the oil literally gets pushed past the guide, down the stem and drips right into the cylinder. And bad guides also smoke on startup too.

[Slow4]

Let me correct you before we go and give a bunch of bad information. Blue smoke under LOAD is "USUALLY" worn rings/bores or both.bad PCV with give similar symtoms. Blue Smoke under hard DECELL usually means valve guides...and why is this? Because you have 8 sucker-******s making GOBS of negitive pressure and when that throttle plate snaps shut theyre goning to pull air from anywhere possible IE valve guides; Valve is open, pistons going down, negative pressure less then the pressure inside the Valve cover so some bad vavle seals with a sloppy guide is when the oil literally gets pushed past the guide, down the stem and drips right into the cylinder. And bad guides also smoke on startup too.

In other words, PCV is a small factor in oil consumption under load and off load decel...yes?

This is why I came to the conclusion my valve stem seals and cylinder head gaskets will need to be replaced; this was AFTER replacing the VCGs and PCV did nothin to slow my oil consumption with the above smoke symptoms.

A compression test only gives you a glimpse of the cylinder health whereas a leakdown plus borescope exam gives you a better sense of what's up with your cylinders. I've personally seen and watched all my cylinders get the leakdown treatment by a certified tech....it's a pretty neat process and WAY more in depth that compression.

[RPMtech147]

In other words, PCV is a small factor in oil consumption under load and off load decel...yes?

This is why I came to the conclusion my valve stem seals and cylinder head gaskets will need to be replaced; this was AFTER replacing the VCGs and PCV did nothin to slow my oil consumption with the above smoke symptoms.

A compression test only gives you a glimpse of the cylinder health whereas a leakdown plus borescope exam gives you a better sense of what's up with your cylinders. I've personally seen and watched all my cylinders get the leakdown treatment by a certified tech....it's a pretty neat process and WAY more in depth that compression.

When the PCV fails It prevents trapped gasses from 'Normal Blow By' from getting out of the crank case. That pressures gotta go some where, a lot of Das Autos will pop the Dipstick just from the pressure but when thats not enouph it goes right back into the cylinder that's on the intake stroke. Plugged PCV's pop seals and get past rings, more so at High RPM.. I don't know if accell/decell has anything to do with it...

Compression tests don't mean dick for oil control rings. They measure, hear it comes, COMPRESSION YAAAAA!! otherwise theyd call it an oil-control-ring test lol, sorry Im a dick.

Leak down tests are fun and all, impressive to those that haven't been fixing(and breaking stuff) for 20 years. If you want to know if a cylinder is f*cked and you dont have bore scope, take a regular compression tester hose, pull the schrader valve, hook up 150psi shop air to a hole.(this method works wonders for holding up valves while changing the springs on OHV V8's) If it blows off the oil cap and the dip stick shoots a hole in the hood, then you need a new motor, or at least massage the insides where she really likes it. If the motor spins over like its running that hole is good.

It should stop spinning and balance at BDC Compression with air in the cylinder, if there's air coming from the intake, bad intake valve/seat, same for exhaust....and if there's air coming out of the radiator cap, its moving through the head gasket...NOTE, I have seen engines blow just the part of the head gaskit around the oil passage from bottom to top and use oil in that fashion. I, well WE also found the motor in a 1965ish, was it, Lamborghini superleggera had couple if the main bearings in upside down so the oil feed hole was on the wrong side causing excessive smoking...Bizarre, ran ok, had good oil pressure somehow with those passages blocked it was pushing oil elsewhere. I wish I could remember the details better. It's acceptable on a motor with high mileage to have just a small amount of air coming both the intake and exhaust while at both valves are closed, that's really your 'Leak Down', and just a bit past the rings as well...a new motor will literally fill up and be almost silent.

Holey shit thats all I got, Question comments, criticisms...Maybe Ill read in the AM, its been a long ass day....

[B6B]

i haven't got to checking the pcv yet, the consumption has been the same since i bought the car, only the smell and smoke when i come to a stop is new. and i never noticed the slight pingy noise before a few weeks ago. i had my brother drive behind to see if he saw it under acceleration and he also only noticed it when we would come to a stop. a little black soot under heavy accel, but no blue. gonna check my plugs too, see if theres any warning signs or wear, i have no idea if they've ever been changed or not. i know i have a slight leak on the right valve cover, but this comes straight out the tailpipe. im not concerned with the consumption so much, but the smell is very noticable in the cabin if i got the windows open, little embarrasing at times.