Excessive Oil Use for RX-8
 

Using around 22 ounces of oil every Fuel tank, that is almost a quart. The driving it normal. We do not see any leaks anywhere and the intake it free of oil. Any explanations or things to check? Engine runs strong and starts easily.

And, is their any chance this has ANYTHING to do with the APV? When I go over 7500RPM it blows out a cloud when he lets off the gas for about 5 seconds. But it still uses the oil even if I do not approach the high RPMs

Sounds very much like he is sucking the oil into the intake, which certainly would produce that kind of oil consumption.

There is likely a vacuum problem somewhere that he needs to solve.

All the vacuum lines seem to be in correctly. Also, an Oil catch is installed. It is less than halfway on the dip stick after I fuel tank maybe 250 miles

Just because the vacuum lines are secured doesn't mean there isn't a vacuum problem. One could be split, leaking, cracked, a gasket could be pinched, a line could be hooked up wrong, etc...

Does it smoke when you first start it

So I am on the same page. You are talking about these on the picture, correct. Make sure there is no crack in the line and such. Am I missing any other one?

I don't see any smoke when it first starts.

If that diagram matches his model year design (04-05 was different from 06-08 which is different from 09-11), then yes, that's the right one to start checking through.

That's a lot of oil without a leak

Is the tune stock? IE no MOP table alterations?

I can't think of a scenario that vac would pull it into the APV area and you wouldn't see it in the intake as well...

I would be tempted to think you have an oil control ring issue....but would expect it also at lower RPM's...or on startup when the oil pressure is higher

I have used that much oil on the track...so the pump can output that amount....just not in normal driving conditions

I have been driving at like 65mph to work and back. Does the same thing.
I have a ported engine, actually have a Cobb with a MM tune. I recently cleaned the SSV also.

Wait, is this your car or your friend's car?

I see you switched pronouns on us...

If you haven't recently changed the MOP tables it shouldn't just start doing this. How long has it been eating oil ?

LOL....trying to figure that out as well.....

I may switch back to the stock map and check the usage. Could be the map.

Indeed. My car. Head was somewhere else at the time.....

MM's map will burn a lot more oil, but not 1 quart over 300 miles by itself. On his map, I was burning 1 quart every 800 miles with pretty active use of the rev range.

Still, swapping to the stock map to check burn rates is useful info.

FYI Mazda has an updated oil neck/vacuum chamber assembly that is supposed to help reduce oil getting sucked into the intake.