What does this oil use pattern indicate?

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You also want to be able to punch it if the need arises. I'm sure we all are killer drivers here, but putting the tranny back in gear takes time. In emergency situations milliseconds count. Self-preservation dictates to leave the vehicle in gear while it's moving -- except during shifting and right before stopping.
 
I always downshift! What is the point of haveing a manual trans. if you do not use engine brakeing. I drive too agresive when on back roads to not use engine brakeing to help me get the car into and out of the corners! Brakes are for emergency stops and that last little bit at the stop sign!

In the 24,000 miles i have owned my Camry I have only used 1/3 of a quart of oil and I drive it like I am in the WRC!! I tickle the redline every time I drive! I can actualy break all the speadlimits in my area with out even shifting out of 1ST gear. I will have to check but I think I can do the speed limit on the interstate in first as well!
 
quote:
Originally posted by brianl703:
I've never heard of a car that will go 55MPH in first.
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Lamborghini Countach would...
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I'm going to interrupt the current conversation flow by returning to my question; I don't see evidnece of significant oil use through the PCV system. The Neutra didn't seem to have any really big impact on things, so perhaps this is not a "sticky ring" type of problem(??)

I might be willing to try mixing a little 10W40 in next time, but RedLine specifically advises against its use unless there are high oil temperatures. I don't have an oil temp gauge, but I do have an IR gun and it shows 183-195 on the dual-remote body when I get home in the garage.

Any thoughts?
 
Hmm, that sounds like the fresh air intake to the PCV system, usually attached to the valve cover. Rarely does oil ever show up here unless we're talking about a poorly-designed PCV system.

The PCV valve itself should be attached (by a hose) to the intake manifold, providing it with engine vacuum. If oil is being picked up by the PCV valve, it will be sucked into the intake manifold.
 
Yeah, I see what you're saying. However, that was the PCV valve I replaced that is attached to the valve cover. Then the hose goes from it to the airbox. In its general design, it's just like an American V8 pickup was (don't pay attention to the newest ones); the breather hose empties into the airbox before the throttle butterfly.

The 1st-generation Neons had a "dual-port" valve cover, which I guess means it had a fresh-air intake. The 2nd-gens, however, only have this one.
 
My V8 Mustang (which being a 1988 model is probably very similar in config to an old V8 pickup) has the breather hose like you describe, attached to the throttle body and emptying into it, but it also has a PCV valve which is connected to the intake manifold.

In normal operation, the airflow on the PCV system on that car is from the airfilter, to the breather hose, to the valve cover, to the crankcase, to the PCV valve, to the intake manifold.

If you pull the PCV valve with the engine running on your car, is there vacuum at the end of it? (This is also a good test of general PCV valve function).
 
I guess I'll have to check tonight. If there was a vacuum, the airflow would be "backwards" to what I'm accustomed to. The other PCV systems I'm thinking of (mainly Mopar) definitely go from the valve cover to the airbox upstream of the throttle butterfly, because there is black sooty stuff from the breather on the outside of the airfilter there.

To me this is the more sensible way of making a PCV system simply because if you ran the breather from the valve cover to a point downstream of the throttle butterfly, you would be either bypassing the MAF sensor or gunking it up, and you would also be trying harder to suck stuff from inside the crankcase into the engine when it's idling (because the throttle is closed) and not so hard when it's at WOT (because the throttle is open). If you add to that the ability to draw air in around the throttle butterfly (which is what you have if there's a PCV intake upstream of the throttle butterfly and an outlet downstream of it), you'll have an engine running at high idle (that's WOT and no load) all the time.

EDIT: Just out of curiosity, what is the reason for/advantage of drawing fresh air into the crankcase? I thought the idea was to vent/draw vapors out of the crankcase which are there primarily as a result of blow-by.(?)

In any case I'll re-check this Neon for positive tonight, though I expect no surprises.

[ June 06, 2005, 05:35 PM: Message edited by: bulwnkl ]
 
quote:
Originally posted by bulwnkl:
EDIT: Just out of curiosity, what is the reason for/advantage of drawing fresh air into the crankcase? I thought the idea was to vent/draw vapors out of the crankcase which are there primarily as a result of blow-by.(?)
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My understanding is that is the "Positive" part of "Positive Crankcase Ventilation".

The reason for doing it that way is to ensure that crankcase vapors are removed.

Otherwise, if you just waited for the levels of crankcase vapors to build up until they started coming out of the breather, I can see two problems:

1)There would still be a crankcase full of this stuff when the engine was shut off, which will eventually get into the environment as the engine stands idle.

2)These crankcase gasses would still be present to cause the oil to be contaminated that much sooner. Implementation of PCV was perhaps one of the biggest reasons that oil change intervals started getting longer.
 
quote:
Originally posted by bulwnkl:
If you add to that the ability to draw air in around the throttle butterfly (which is what you have if there's a PCV intake upstream of the throttle butterfly and an outlet downstream of it), you'll have an engine running at high idle (that's WOT and no load) all the time.
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The PCV valve is a metered orifice. You can think of it as a controlled vacuum leak. It is spring-loaded so that at high intake manifold vacuum, the orifice is smaller, and at low intake manifold vacuum the orifice is larger. That way, there is always a controlled, consistent flow of air into the intake manifold. This is why the PCV valve should be replaced on a regular basis--the spring gets weak and the PCV valve doesn't flow as it should. Faulty PCV valves have been known to cause idle problems!

Remove the PCV valve from the end of the vacuum hose, and oh yes, it'll idle very high, if the engine doesn't stall.
 
The PCV valve is attached to a piece of tubing that runs over to the airbox. It has a piece of foam on the end (in the airbox, in a little plastic "housing"). I don't see particular darkening of either the foam nor the air filter in the area where the PCV system "vents" into the airbox. I hope that description is helpful; it doesn't look that good now that I read it over.
 
quote:
Originally posted by brianl703:

quote:
Originally posted by dkcase:
I'm sure that soon the black box will upload the coasting information to a satellite link and you'll get a ticket in the mail.
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I'm not sure how they enforce it BUT it makes sense if you consider that the engine could stall while you are in neutral with the attendant loss of (1) power steering assist and (2) vacuum brake boost.
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I'm ALWAYS telling my friend that, he always coasts to stops in neutral. I say, what if the truck stalls, you lose power brakes and power steering. He just chuckles.

I had a bad experience (well, just startling) at 16 in my first truck. Going downhill, for some reason took it out of gear and let the clutch out. Truck promptly stalled, all I noticed was loss of power assist, got freaked out and put it back in gear and let the clutch out. Luckily I was just coasting down a hill, but it was pretty scary to a new driver
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Brianl703:

Well, you're right! I found the second port and hose, which means I have some bad info about valve cover differences or wrong model-year runs or something. But anyway, I guess I'm just getting senile and doing too much remembering of old stuff and not enough remembering of "new."

So, the formerly-hidden hose that goes into the intake downstream of the throttle butterfly has clearly had some fresh oil in it. I'm not sure how to gauge how much, but it is fresh-looking and not carbonaceous or sooty.

It is unclear to me whether there is anything I can do about oil consumption from this source other than drive at low rpm. The port from which this air is drawn is low and on the end of the valve cover. The valve is very roughly 25,000 miles old, but historically I've seen some consumption since we got it.

So, perhaps I should stop looking and write this consumption off to a poor breather location. There must be some amount of blow-by as well, though, to explain the usage differences brand to brand. Thanks!
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