First off current mods/spec (that are relevant):
2.5l duratec swap
mishimoto occ
vented occ (generic)
short ram intake
factory k04 @231k miles (being replaced december)
Current OCC setup (Note: I still have the factory pcv plate instead of the damond):
View attachment upload_2024-10-20_1-57-26.webp
So the observed issue I'm seeing is under full load, and doing back to back runs at full boost or WOT (give er take 2-3), I do get oil spewing out of my dipstick. The worst I've had it was when I was in Alabama doing back to back runs at WOT, about 7ish runs until I got back to see tons of oil being lost from the dipstick to the point I had to fill up about half a quart. Thing is, the car feels fine with no observed performance issues. It's just when I really push it does this happen.
I have removed the brass filter off the vented catch can which definitely helps when doing test runs, but I'll still get the occasional oil spew, but definitely not as much, but still not normal from the dipstick I presume.
I have attempted to start the car with the oil cap open and air does come out, not the craziest amount though. In my head I assume that's normal since this is a positive crankcase pressure system. I'm not saying I know better, so I'm open to be proven wrong since I'm still learning and this is the first car I've seriously dug into trying to learn. Compression numbers are all 180 across all 4, have not done a leakdown test yet due to the lack of an air compressor.
[My thoughts moving forward]
My current plans is to replace the turbo which was planned quite a few months ago, but seeing this issue makes me wonder if I should instead invest in a PCV plate instead to use the extra pcv holes. But considering this is still the stock turbo, pushing factory boost, I assume it shouldn't even be this bad from the dipstick. Engine runs perfectly fine, it hasn't given me any stuttering or weird noises, it's just strange. My assumption was a possibly stuck pcv valve from a separate thread that raider replied to: https://mazdaspeeds.org/index.php?threads/pcv-excessive.16514/
Another factor is that this is the 2.5l which I'm not sure how much it affects the dynamics of the PCV system, but maybe the slightly bigger displacement could be making more boost than I think it is? I'll have to do one of those runs at those same speeds with my obd hooked up to double check.
But anyway, I'm just airing my thoughts and would like to know what someone else things about them.
2.5l duratec swap
mishimoto occ
vented occ (generic)
short ram intake
factory k04 @231k miles (being replaced december)
Current OCC setup (Note: I still have the factory pcv plate instead of the damond):
View attachment upload_2024-10-20_1-57-26.webp
So the observed issue I'm seeing is under full load, and doing back to back runs at full boost or WOT (give er take 2-3), I do get oil spewing out of my dipstick. The worst I've had it was when I was in Alabama doing back to back runs at WOT, about 7ish runs until I got back to see tons of oil being lost from the dipstick to the point I had to fill up about half a quart. Thing is, the car feels fine with no observed performance issues. It's just when I really push it does this happen.
I have removed the brass filter off the vented catch can which definitely helps when doing test runs, but I'll still get the occasional oil spew, but definitely not as much, but still not normal from the dipstick I presume.
I have attempted to start the car with the oil cap open and air does come out, not the craziest amount though. In my head I assume that's normal since this is a positive crankcase pressure system. I'm not saying I know better, so I'm open to be proven wrong since I'm still learning and this is the first car I've seriously dug into trying to learn. Compression numbers are all 180 across all 4, have not done a leakdown test yet due to the lack of an air compressor.
[My thoughts moving forward]
My current plans is to replace the turbo which was planned quite a few months ago, but seeing this issue makes me wonder if I should instead invest in a PCV plate instead to use the extra pcv holes. But considering this is still the stock turbo, pushing factory boost, I assume it shouldn't even be this bad from the dipstick. Engine runs perfectly fine, it hasn't given me any stuttering or weird noises, it's just strange. My assumption was a possibly stuck pcv valve from a separate thread that raider replied to: https://mazdaspeeds.org/index.php?threads/pcv-excessive.16514/
Another factor is that this is the 2.5l which I'm not sure how much it affects the dynamics of the PCV system, but maybe the slightly bigger displacement could be making more boost than I think it is? I'll have to do one of those runs at those same speeds with my obd hooked up to double check.
But anyway, I'm just airing my thoughts and would like to know what someone else things about them.
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