P0521 with low oil pressure

Tech discussions on the L77 6.0L V8.
bstoner
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Re: P0521 with low oil pressure

Post by bstoner »

Minimium spec would be 135 kpi at 1,000 rpm engine fully warmed up so you are low.
2014 Caprice PPV, 6.0L, BTR Stage 2 Cam, 3.45, 3" exhaust, Rotofab intake, Chris Henry tuned, future LSA....
Caprice ltz
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Re: P0521 with low oil pressure

Post by Caprice ltz »

change to #12612289
Change to 10w40
Change the secondary oil relief valve
ohms on the #3 pin = 50

Still I have the issue.

I can't find any mechanic have the oil pressure gauge.
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Mooseman
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Re: P0521 with low oil pressure

Post by Mooseman »

How did you determine that you have just 56kpa (~8psi)? Was it using the sensor and ECU data or did you use an actual mechanical pressure gauge? If you haven't used a separate gauge, I suggest you do that before anything else. You have to confirm what kind of pressure you actually have before anything else. Test kits aren't that expensive:

https://www.amazon.ca/8MILELAKE-Engine- ... 160&sr=8-5
2011 Caprice PPV, former RCMP test vehicle, never put into service
Build Thread: http://www.newcaprice.com/forum/viewtopic.php?t=2419
Caprice ltz
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Re: P0521 with low oil pressure

Post by Caprice ltz »

56 kpa by sensor.

And now by mechanical pressure gauge.
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bstoner
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Re: P0521 with low oil pressure

Post by bstoner »

- Bad o-ring in pickup tube
- Pickup tube blocked/kinked, hitting bottom of pan
- Bypass valve bad/leaking
-Secondary bypass valve in pan bad/leaking
- DOD valley cover leaking
- Bad bearing clearance
- Clogged oil filter

If it was me I would install a new oil pump, make sure the valley cover is sealing the towers (or rivet the towers shut), make sure the oil bypass is plugged/blocked off in the oil pan, and install a new filter. Check pressure. If still low, then pull motor and start checking bearing clearances.
2014 Caprice PPV, 6.0L, BTR Stage 2 Cam, 3.45, 3" exhaust, Rotofab intake, Chris Henry tuned, future LSA....
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Mooseman
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Re: P0521 with low oil pressure

Post by Mooseman »

Was that at idle? What kind of pressure are you getting at 1000 RPM? 2000 RPM? 3000 RPM?

The pump you installed looks to be a stock high volume unit correct for this engine so I don't think it's a pump issue. If you are getting low pressure, I don't think the pump or its bypass is to blame.

I'm thinking that the pickup o-ring may have been damaged during install, the bypass in the oil pan is defective and bleeding oil pressure (common issue) or, at worse, the engine bearings are so worn that they are bleeding a lot of oil pressure.

As I understand it, you replaced the DOD components retaining it and working? Most people delete this system and deactivate it with a tune since it is a failure prone system. Once the oil pressure issues are solved, you should get it tuned to turn it off. This will prevent failures in the future.
2011 Caprice PPV, former RCMP test vehicle, never put into service
Build Thread: http://www.newcaprice.com/forum/viewtopic.php?t=2419
Caprice ltz
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Re: P0521 with low oil pressure

Post by Caprice ltz »

Is 30 psi still consider low!!

At 1000 RPM with temp 100 C.
bstoner
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Re: P0521 with low oil pressure

Post by bstoner »

Oh shoot! I completely misread the gauge. I thought it was 30 kpa! Ignore what I said! Your oil pressure is fine. You have an issue with the sending unit.
2014 Caprice PPV, 6.0L, BTR Stage 2 Cam, 3.45, 3" exhaust, Rotofab intake, Chris Henry tuned, future LSA....
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Mooseman
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Re: P0521 with low oil pressure

Post by Mooseman »

I have found on other vehicles with DOD that if it doesn't go over 40 psi while driving, it throws the code. New oil helps for a while until it thins out and comes back. If at 1000 RPM it stays at 30 PSI using the test gauge, it's low.
2011 Caprice PPV, former RCMP test vehicle, never put into service
Build Thread: http://www.newcaprice.com/forum/viewtopic.php?t=2419
Caprice ltz
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Re: P0521 with low oil pressure

Post by Caprice ltz »

Thank you so much for your reply and help.

Why some mechanic said ( low oil pressure ), and should be change the crank with bearing!!!
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