RIWWP

iTrader: (2)

Yes, it is part of the engine core. The only method of diagnosis is an engine compression test. Since you only have a month left on it, I'd honestly get back in there and get the compression test done, even if that isn't the problem. You don't want to be sitting on an engine that is just failing with a month left, and then a month after it passes you find out it's done.

It's entirely worth the cost of the compression test if it turns out you have a solid engine.

If you explain the issue to the adviser and techs as well, they can specifically look for signs of it during the test.

t.swain

https://www.rx8club.com/series-i-trouble-shooting-95/minimum-compression-warranty-replacement-233527/

I actually just had a compression test done. And although my starter was awful, I still passed the compression test. I've replaced the starter and the spark plugs since then, though.

Not to mention that dealership charges me 245 for the test and they charged me 150 dollars when I asked them to diagnos this oil problem. They didn't believe me. Changed the oils. Told me not to touch it. Bring it back in when the light comes on and charged me 150
Would rather not go back there.

t.swain

Each end of the UIM
Sorry about the size.

RIWWP

iTrader: (2)

The differences between the plugs suggests it's specific to 1 housing. All are filthy and clearly old from the discoloration of the hex nut, but the left two are clearly oiled. Any idea which housing the 2nd plug from the left came from? That's likely your problem housing. If the left 2 were from the same housing, then I'd say it strengths that impression, as those two plugs are the ones with oily moisture, and the leading plug (lower, one with 4 divisions of the ring around the tip) being the more oily suggest you have an internal oil leak.

t.swain

If I remember correctly, the two oily ones were from the second rotor housing. The trailing plug all the way on the left was the last plug I pulled ( I remember because of the crud) and they were the highest ones up. The leading plugs could have been mixed up, but I doubt it.

Could you give me an idea of everything that could cause an internal leak other than the oil ring failure?

RIWWP

iTrader: (2)

That's the only real option. The only other oil that gets into the housing combustion area is the injected oil from the OMP system, and it's incredibly low volumes. The OMP is a stepper motor, like a gear where the "pocket" of each gear is how the oil is moved, and delivered to the oil injector lines, where engine vacuum pulls the oil into the combustion chamber in the housing. 2 injectors per housing, pointing to the outside. Even a solid vacuum puling oil directly shouldn't be able to pull that much, and it's still 1 pump for both housings, so it couldn't fail for just 1 housing.

The oil control rings are inwards from the rotor's side seals, and help trap the oil that is pumped through the e-shaft. The only real method of that oil escaping is if the oil control ring fails. Usually, when it does fail, the paired coolant seal fails as well (same concept and practice here), and you will see the coolant burn off before the oil burn off. But not always. A compression test SHOULD reveal a loss of compression.

t.swain

If I'm understanding everything correctly the only way the dealer could diagnose an internal oil problem is via a compression test?

Do you think my last compression test wasn't valid since the started cranked so low?
I don't understand how I'd have an internal oil leak, which you said would be accompanied by low compression, but my engine still passed the test at low cranking rpm. Leading the dealer to tell me "you have exceptionally good compression actually"

:/

RIWWP

iTrader: (2)

Hmm, that would contradict this theory. How long ago was the test?

I wonder if the leaking oil could have falsely boosted compression?

The problem is that there are VERY few places for oil to come from or go, and the evidence is pointing at internals...

t.swain

This compression test was about a week and a half ago. No more than two weeks.
I'm aware of the few places for oil to go which is why I needed expert advice from the forum.
I'm dumbfounded.

Could the oil consumption have been because of the terrible ignition system I had? Awful starter. Foulded plugs. Probably coils and wires too. I should have BHR coils and wires within a week or two. Just a culmination of these things?

Side note, how awful is it to drive my car with this problem occurring? She feels like she runs good. And the spark plugs definitely helped today. Still getting misfires though which is partly the reason for new ignition kit. But right now oil is my biggest concern.

bse50

Ignition components have nothing to do with oil consumption.
OMP stuck open, oil control ring or any of the aforementioned reasons RIWWP tried to explain.

There's a huge chance you may need a new engine, period. Either find a competent mazda mechanic that knows that rotaries can fail for causes other than compression loss or just buy a remanufactured engine from mazmart. It's as simple as that!

t.swain

I guess I'll call around and find a better Mazda dealer and see how much it will cost me to diagnose.

Thanks for all the help. It's very much appreciated

Lastly, pretty sure this plays no factor since I've read it's a dummy gauge some time ago, but my oil pressure gauge is about 4 lines over half.

t.swain

Uhm, could this be my problem?

https://www.rx8club.com/series-i-tech-garage-22/high-oil-consumption-due-wrong-air-intake-hose-series-1-only-186526/

The dealer I bought the car from a year ago said that they engine had recently been replaced.

RIWWP

iTrader: (2)

Yes, it's a dummy gauge, "Yes" or "no". The exact position of the needle is unimportant. If it dips while running, specifically at idle, there is serious internal damage starting. It's Mazda's change to "consumer friendly" gauges from the real gauges of yester-year. Too many panicked owners coming in because their gauge was reading higher or lower than normal, when all it happened to be was a viscosity change, either with a different oil or changing weather. Unfortunately, their tolerances are much too wide, for oil and water.

By the time it moves, it's too late, the damage has already started.

Great find.

It's possible? It doesn't specify how much is "high oil consumption".

It seemed like your description had meant that the oil consumption is a much more recent problem with no changes since it was fine, so

It does mean a few things:
A) It IS possible to pull more oil through the OMP than intended
B) If you do not have the incorrect hose, then it means that there could be a blockage which is causing the significant OMP pull

t.swain

I'll check to hose on my lunch.

As far as blockage, where is the most likely place it will be?

RIWWP

iTrader: (2)

It's new ground for me, so not really sure. The TSB suggests that a blockage in that hose would cause the same problems, but what might block it is certainly up for debate. Oil sludge is about the only blocking substance that should be able to get into your intake that wouldn't also destroy your engine (debris like rocks or such), but against engine vacuum, I'd expect engine vacuum to win that tug-of-war, and any blocking would be incredibly brief.

t.swain

At this point, to me, it seems as if the hose is the most plausible thing. Seeing as my engine has good compression still.

Idk, probably just wishful thinking because this would be an easy solution to a huge problem. Too good to be true.

RIWWP

iTrader: (2)

Simple problems usually have complicated solutions, and complicated problems usually have simple solution.

It's the nature of house a single simple failure can cascade through many systems. Common widespread problems can usually easily be traced to a single point, a single problem can have numerous possible sources.

HiFlite999

iTrader: (2)

To clarify: "If you do not have the incorrect accordian hose, then it means that there could be a blockage in the vaccum hose running to the OMP which is causing the significant OMP pull."

It's explained (indirectly) in this thread:
https://www.rx8club.com/showthread.php?t=225321

RIWWP

iTrader: (2)

Thanks!

t.swain

as far as the service bulletin:

Just checked the accordion. I definitely have the 3 hole one which is the correct one.

Thanks for the link hiflite. I shouldn't need to flush the oil lines because if those were clogged, I'd be consuming very little oil, correct?
Next step is checking if the vacuum line is clogged.
How would you recommend checking to see and them re,icing a clog in it?

t.swain

How do I tell if omp is turned up too high?

HiFlite999

iTrader: (2)

I'm not suggesting there's a clog in the lines from the OMP to the rotors - that would cause less oil to be used. There *might* be a blockage in the vacuum line which runs to the OMP, that would cause oil use to increase. Or there's an error in vacuum hose routing. Or your engine is screwed internally.

t.swain

Okay. I'll look for a blockage in the vacuum line that runs to the OMP.

Another guy I talked to said you can adjust the setting of the OPM using a set screw on this RX7
Is this the case with the 8? I gave it a look today ad judging by the electrical connection, I'm gunna say it's adjusted electronically.

RIWWP

iTrader: (2)

Yes, the OMP is based off of a digital table in the ECU that uses load and RPM to determine how far and how often to advance the stepper motor in the OMP that delivers oil to the vacuum for delivery into the engine. The only real method to increase the OMP rate is to change this table as part of a reflash. It is one of the staples of AccessPORT reflashes, but still only 1/10th of your oil usage.

ASH8

It really has all been said..

If you are going through that much oil the car would be fuming out of the exhaust pipe, more like a old 2 stroke engine.

Plugs are quite oily, but, I was expecting worse...

70K, I call this one Oil Control Rings more than likely, sorry, apart from Vacc Lines and or MOP (OMP), it cant be anything else..

New engine.,,,if OCR's