Oil Pressure Drop Under Braking?
#1
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Oil Pressure Drop Under Braking?
Like the title says, the other day I noticed that my oil pressure (dummy gauge) would drop under hard braking after extended high rpm cruise, made worse by downshifting and engine braking while stopping.
Level looks good, added 3/4qt to put it above the full line, and problem persists.
Any ideas?
Level looks good, added 3/4qt to put it above the full line, and problem persists.
Any ideas?
#6
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Like I said (I think), I did check the oil level, noticed it was a tick under the full mark, filled it up to full, searched, then added an additional 3/4qt as recomended. The problem still persists, and I am just concerned considering it's a semi fresh rebuild (has about 2.5k miles on it). I have owned the car for five years and autocrossed it heavily, and have never noticed it before.
#11
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Since the motor is under minimal load at that point, the low pressure is not ideal, but it is not a major concern. If it were a big problem, Spec Miatas would be popping motors due to oil starvation left and right.
#12
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Well, from my understanding the pressure has to drop below 7psi for the gauge to fall. Regardless, the gauge has started to drop at a lower than idle rpm, like 500-800rpm.
Looks like a new oil pump is in store.
Looks like a new oil pump is in store.
#13
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I used to have a 20psi oil pressure warning light in the black car and it would flicker under very hard braking in certain corners. If you are seeing a drop to <10psi you have something else wrong.
#15
Did you even read the thread? Here, let me help you out.
Level looks good, added 3/4qt to put it above the full line, and problem persists.
Like I said (I think), I did check the oil level, noticed it was a tick under the full mark, filled it up to full, searched, then added an additional 3/4qt as recomended
#16
I wanted go use a 1 qt Accusump, but Canton (maker of Accusump) told me that anything smaller than a 2 qt wasn't enough. They run a 2-qt on their Miata.
I'm running a 2-qt now. It is kind of nice to let ~20-25 psi of oil circulate the engine for 5-10 seconds before starting the engine. Likewise, it is nice to see that oil pressure never drops below 25 psi on track.
#18
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Right now my guesses for the culprit are either a bad sending unit, or the bypass valve being partially stuck open (although my pressure shoots right up on startup).
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