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I've got a 99 Z28 and I'm putting 468.3 to the wheels N/A at Colorado Springs altitude. Is it normal for a high-output LS1 like this to slowly 'eat' oil? My low oil indicator light came on today and I am not leaking anywhere so it must be eating it slowly. I am coming up on 3,000 miles since my last change, but I've done a few changes (all at 3,000 mile intervals) and haven't ever run low before this.
PCV on LS is dirty, dirty. I run a catch can on everything LS. Start there and see how much oil ends up in that. The rest is likely a mix of valve seals/guides, rings, etc.
How "low" is an F-body when the indicator comes on?
Mine have all used some, but that's usually a quart or a little more in 3000 miles. I don't know how low it has to be to set off the light but if it's 2 qts or more I would be a little concerned and keep a close eye on it.
One thing to be aware of if some brands of filters hold more oil than others, so be sure to check the level on the stick after a change and don't just assume 5.5qts will fill it.
I always run 6 qts per oil change anyway just to be safe.
A catch can won't really help as far as keeping oil in the engine, but it will help in keeping it out of the intake manifold, intake runners, and combustion chambers. It will be trapping "lost" oil which should be disposed of, do not dump it back into the engine.
I will be doing an oil change tomorrow and I will be changing my plugs also just so I can see if anything is getting into the combustion chambers. I have no idea how low it has to be to turn set off the light, but I turned the car off and haven't had a free second to even check the dipstick. I will post more info when I get under it tomorrow
When you get underneath the car, look at where the low oil level switch is located in relation to the bottom of the pan (on opposite side from drain plug).
It is best to check oil level at each/every gas fill (not just to check level, but to observe condition of oil).
If changing the oil anyway, note how much comes out..F-bodies are getting up there in age and you could possibly have a sensor that is misbehaving. And I agree with what was said above about filters holding differing amounts..do you fill with a certain quantity, or to a certain level on the dipstick? I think to truly have a controlled experiment, change the oil, warm the vehicle up(basically filling the filter), let it sit and all oil drain into the pan for an hour or so and then fill according to the dipstick. Then you know you have a "full" engine. You could be tossing x.x quarts in there and actually be "low" from the start.
Less likely, but oil can push into the cooling system..though usually you will see evidence of the opposite.
You could empty the Engine of oil and then check the resistance in the sensor with a Ohm meter and see if is open or closed. Then fill your car and check it again. See if the sensor is acting up. If the sensor is open when empty and closed when full it is working properly. If it is working do a compression test and see if the your rings, valve seals, etc. are working properly. You can also pull the oil fill cap off run it and see how much blow by you have.
I haven't been able to change the oil yet as life got very hectic, but I did have a few spare seconds to check the dipstick. the oil was well below the operating range. This tells me the sensor was working, but that my engine is eating 2+ qts within 3,000 miles. I have clean exhaust and the engine only has 12,000 or so miles on it. any ideas?
So I have pulled all but the rear passenger spark plug. They all look the same except the third plug back on the pass side which is darker. I've attached photos. Could this discoloration be caused by oil in that chamber?
That, plug wire, plug itself, gap..injector could be a little leaky giving more fuel at idle or dumping when off. But in my experience, usually a significant amount of oil in there will actually be oily on the plug, if that makes sense...like foul the plug and not just look rich/carboned up.
Free and quick, swap the coil and wire from another cylinder, swap that plug to yet third unrelated cylinder. Run it, and see what you end up with. I think this is unrelated to your oil consumption but I can't say for sure. I still think your PCV is probably most likely the culprit.
Im beginning to wonder if I did not put enough oil in during my last change and .25-.5qt of oil were taken through the PCV. That would explain the 2+Qts low
03-03-2016, 09:56 PM
Probably a stupid question but....? 
