Burning Oil but all tests good

CT_MS3

CT_MS3

Greenie N00B Member
I am burning about 1 qt/1000 mi or more and I'm at a loss at to what to do next. It's definitely coming out of the exhaust, it will smoke during the idle test and the tips get black shortly after cleaning them. There are no leaks, I park in the same spot everyday and never see any drops. I have been babying the car not really hitting boost too much but nothing seems to be helping. During the compression test the threads on sparks plugs for C2 and C4 were pretty black with what I'd guess is oil.

Year/Make/Model: 2010 Speed3
Mileage: 170k
Recent Repairs:
Compression Test: 178, 170, 172, 170
Leakdown: ~3% on each cylinder
Replaced PCV valve, intake cleaning done. Damond OCC installed
Turbo replaced with CWturbos rebuilt K04. Damond oil restrictor banjo bolt and running 5w40 oil.
 
Corksport 3" performance air intake and an OTS cobb tune. The previous owner has had that tune on the car since early 2016, oil issue has only been going on for the last 1.5 years.
 
I was ready to upgrade to the V3 (still have a V2 from the previous owner) and get a freektune but wanted to solve this oil issue first, didn't think my tune was suddenly causing the oil loss. Didnt want to drop the $$ on that if my engine was toast.
 
Based on the compression test and leakdown I wouldn't say the engine is toast. Are you sure the pcv valve is good? The two things I would think are the culprit would be the turbo or pcv valve but you have replaced both. You should also look very carefully for leaks could be hitting exhaust and burning off
 
upload_2023-10-18_17-56-31.jpeg Here’s my exhaust tip after taking a paper towel to it to show the oil buildup. The large hoses off the intercooler were clean when I did the compression test. The new PCV has been on for about 5000 miles. OCC only has a small amount of oil when I empty it, but each time there’s some in there. Could it mean the new valve is already clogged? I figured there would be no oil in the OCC if it’s clogged, or a lot in there if the PCV is stuck open.
 
I am still burning about 1 qt/1000 mi or more and I'm at a loss at to what to do next. It's definitely coming out of the exhaust and not a leak, it will smoke during the idle test and the tips get black shortly after cleaning them. There are no leaks, I park in the same spot everyday and never see any drops. Based on the testing done and parts replaced I am at a loss as to what is causing this oil loss. When I took the spark plugs out for compression testing they had oil on the threads, especially cylinders 2 and 4. I stuck a camera in all the cylinders and 2 looked quite wet and 3 a little wet. Any help is appreciated, feel like I'm throwing money at this issue and nothing is helping.

Year/Make/Model: 2010 Speed3
Mileage: 170k
Recent Repairs:
Compression Test: 178, 170, 172, 170
Leakdown: ~3% on each cylinder (done by XLR8 Performance)
Replaced PCV valve, intake cleaning done. Damond OCC installed (done by TheShopCT)
Turbo replaced with CWturbos rebuilt K04 (done by TheShopCT) Running 5w40 oil. PCV, OCC and turbo have been on for only ~5000 miles
OPR V2 oil pressure regulator to limit turbo oil feed line to 40psi.
Car has been on an OTS cobb tune for 6+ years, this oil issue has been going on for only 1.5 years.
 
I had issues with oil leaking down from what I thought was the PCV plate. 50K miles .Only when running, no drips. Threw parts at it and it ultimately ended up the headgasket.

There could be a solid chance you are simply burning oil. If you take off the turbo manifold, is there oil?
 
I burn probably that much or more, though my car is primarily a track car now - I won't advocate that you ignore it but.... if compression and leakdown are good, and the car seems happy, send it?
 
Haven't taken off the turbo manifold and wont have access to do that for a bit. If the leakdown test is correct at 3% for each cylinder/good compression that would rule out the head gasket? Leakdown test was done 6100 miles ago (March). No oil in the intercooler piping and when I empty the OCC, there's some oil in there but not an excessive amount. upload_2023-11-15_15-25-48.png

Here's the inside of cylinder 2, which was the worst looking one when I did compression testing.
IMG_4273.jpg

I'd love to be able to send it but clearly something has to be going wrong with this much oil consumption. Everything else seems fine on the car but I've been babying it with this oil issue.
 
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Could you have clogged oil control rings? Especially at that mileage. At least one of the guys over the the r/mazdaspeed3 subreddit was able to free them up via some of the stuff that comes in a bottle and cut their oil usage down to a fraction.
 
MacheteJames said:
Could you have clogged oil control rings? Especially at that mileage. At least one of the guys over the the r/mazdaspeed3 subreddit was able to free them up via some of the stuff that comes in a bottle and cut their oil usage down to a fraction.
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Yeah I've seen the posts with AC Delco top end cleaner or similar soak on the pistons overnight or longer. I think this is the best next step for me. Seems easy to do and relatively cheap compared to some of the other work I've had done.
 
CT_MS3 said:
Yeah I've seen the posts with AC Delco top end cleaner or similar soak on the pistons overnight or longer. I think this is the best next step for me. Seems easy to do and relatively cheap compared to some of the other work I've had done.
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Can't hurt anything as long as you change the oil afterwards.
 
My #4 cylinder looked like that when I determined my motor was done. I had clogged oil control rings and worn valve guides. My leak down was not good at all and I was using a qt every 500 miles.
 
Update:
Did a Berryman B12 soak for ~50 hours, rotating the crank every 6 or so hours and pouring more B12 in each cylinder. Made sure the cylinders were dry, put it back together, and started the car up (took a few minutes, and put a little Marvel mystery oil in each cylinder to help out). Idled for 15-20 minutes with some higher revs had some stuff spit out the exhausts. Next emptied out that oil, put in cheaper Walmart oil + filter. Drove the car hard for 20-30 min with highway and fast accelerations in boost. Then changed out that oil and put in Penzoil Plat 5w40 and a new filter.

Only about 250mi in so far but no oil loss. Will keep updating as I hit higher mileage.
 
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Glad to hear that worked out for you.
Thanks for posting the results, seems like something that could happen to anyone, and it seems you have found a reasonable solution.
 
Update:
I am 1815 miles in, with a 400 mile round trip this past weekend, and oil level is still great. Only a very slight dip (~1/8qt at most) which I still see as a win.
Seems like the B12 soak seriously helped my oil loss issue and I’d recommend for anyone as it’s a cheap relatively easy job. I’ll update again when I change my oil in the spring.
 
CT_MS3 said:
Update:
I am 1815 miles in, with a 400 mile round trip this past weekend, and oil level is still great. Only a very slight dip (~1/8qt at most) which I still see as a win.
Seems like the B12 soak seriously helped my oil loss issue and I’d recommend for anyone as it’s a cheap relatively easy job. I’ll update again when I change my oil in the spring.
Click to expand...
that's great to hear - cylinder 4 on my motor seems consistently wet / more plug fouled than the others, I might give that try
 
Any update on this since your oil change?
CT_MS3 said:
Update:
I am 1815 miles in, with a 400 mile round trip this past weekend, and oil level is still great. Only a very slight dip (~1/8qt at most) which I still see as a win.
Seems like the B12 soak seriously helped my oil loss issue and I’d recommend for anyone as it’s a cheap relatively easy job. I’ll update again when I change my oil in the spring.
Any update on this since your old change?
Click to expand...
 
I, also would like to know if there are any updates.
this seems like a reasonable "maintenance" plan if the engine is otherwise healthy and burning oil. Something that is seems like may of use face.
I think, from what I have read here and the "Top End" cleaning posts, that once you notice that you are burning or pumping oil out the exhaust, validate that the engine is otherwise healthy, Compression and Leak down tests, and validate the PVC system is operating properly, that the "Top End" cleaning should be done right away. If it helps, then do it again in a few oil changes.
My thoughts here are, one cleaning like this likely won't get it all, that rings will loosen further while you drive, do it again to try to get the rest of the gunk off. If it works, maybe do it every year after, to extend your engines life.

All that is just a guess, that's why I would like to know what the results are today, please.
 
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