Generation IV Internal Engine 2005-2014 LS2 | LS3 | LS7 | L92 | LS9

Oil pressure random drop

Thread Tools
 
Search this Thread
 
Old 02-22-2020, 02:20 PM
  #1  
Staging Lane
Thread Starter
 
ffjosh's Avatar
 
Join Date: Mar 2011
Posts: 68
Received 4 Likes on 4 Posts

Default Oil pressure random drop

6.0
bored .040
Brand new flat top pistons
ported meling pump
Small cam
New valve train

Idle cold 55 - 60 psi
idle hot 40 psi

Did two 10 min idle warm up cycles no issues.

Weather changed and I was able to drive it today
2500-3000k 70 psi
around 1k 40ish psi

after about a mile which included stopping shifting rpms ranging from idle to 3k (under 50 mph and under 35% throttle) I stopped as I noticed I lost a tool in the road. It sat and idled for about 5 mins.
when I got back my check oil warning was on and it was at 7.8 psi! I drove it down my long driveway around 1200 rpm and it never changed.
No noises, gave it a little rev when I parked it (1500 rpm) and still 7.8.

When I looked back at the data log @2700 rpm I had 72 psi
Later @2700 it had 45 psi

Idle went down to 12 psi

Running 5w30 valvoline for the break in with a wix filter. Any ideas?
Old 02-22-2020, 02:24 PM
  #2  
Staging Lane
Thread Starter
 
ffjosh's Avatar
 
Join Date: Mar 2011
Posts: 68
Received 4 Likes on 4 Posts

Default

I'm going to pull the oil pressure gauge and make sure it didnt get anything in it. My first oil change had some sparkles (seemed normal for a new engine)

Rear main seal is leaking a little. It was leaking a lot but I fixed most of the leak with a better pvc system. Now it's just a few drops.

Oil is right at the full line.

I was thinking of adding a extra quart (bring it to 6.5) and see if that helps
Old 02-22-2020, 05:38 PM
  #3  
TECH Resident
iTrader: (14)
 
SLP IROC-Z's Avatar
 
Join Date: Aug 2004
Location: Salem, NH
Posts: 910
Received 169 Likes on 120 Posts

Default

cut the filter open
Old 02-22-2020, 06:48 PM
  #4  
11 Second Club
iTrader: (3)
 
01CamaroSSTx's Avatar
 
Join Date: Feb 2015
Location: Conroe, Texas
Posts: 5,226
Received 1,901 Likes on 1,374 Posts
Default

Running the stock gauge and sensor I take it.
Check the oil pressure sensor and connector first but that sounds like something went terribly wrong.
Old 02-22-2020, 09:42 PM
  #5  
Staging Lane
Thread Starter
 
ffjosh's Avatar
 
Join Date: Mar 2011
Posts: 68
Received 4 Likes on 4 Posts

Default

Filter is fine

Originally Posted by 01CamaroSSTx
Running the stock gauge and sensor I take it.
Check the oil pressure sensor and connector first but that sounds like something went terribly wrong.
new gm sensor (20 mins on it) using hp tuners to tune it.

Connector was fine I'll get the sensor off tomorrow
Old 02-22-2020, 10:27 PM
  #6  
TECH Resident
iTrader: (14)
 
SLP IROC-Z's Avatar
 
Join Date: Aug 2004
Location: Salem, NH
Posts: 910
Received 169 Likes on 120 Posts

Default

pressure relief valve might be stuck in the pump
The following 2 users liked this post by SLP IROC-Z:
ffjosh (02-23-2020), G Atsma (02-22-2020)
Old 02-23-2020, 12:29 PM
  #7  
Staging Lane
Thread Starter
 
ffjosh's Avatar
 
Join Date: Mar 2011
Posts: 68
Received 4 Likes on 4 Posts

Default

I could not get the oil pressure switch off (my deep well is not at home) so I filled it with 6.5 quarts just to be sure. Check all the lines, fuses ect.

Oil pressure said .8 before cranking
Started it and it still said .8

After 5 secs I turned it off

oil says -2.2 now
started it and still says - 2.2.
said *** it and let it run 10 secs. Went from cold idle 1100 to 800 and never changedchanged it off.

I should have my deep well tomorrow and well investigate.
Old 02-23-2020, 01:23 PM
  #8  
ModSquad
iTrader: (6)
 
Che70velle's Avatar
 
Join Date: Jan 2012
Location: Dawsonville Ga.
Posts: 6,521
Received 3,575 Likes on 2,199 Posts

Default

Do not start the car again. I’d put money on it being the relief spring in the pump. Happening here lately to a couple folks. It’s a boat load of work, but if it were mine, I’d pull the oil pump and take a look. It’s visible through the window on the back side of pump.
The following users liked this post:
ffjosh (02-24-2020)
Old 02-25-2020, 12:22 AM
  #9  
Staging Lane
Thread Starter
 
ffjosh's Avatar
 
Join Date: Mar 2011
Posts: 68
Received 4 Likes on 4 Posts

Default

Been searching but any way to test the oil sender unit? Ohms test I would guess
Old 02-26-2020, 01:10 PM
  #10  
Teching In
 
KT35's Avatar
 
Join Date: Mar 2019
Posts: 4
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by ffjosh
6.0
bored .040
Brand new flat top pistons
ported meling pump
Small cam
New valve train

Idle cold 55 - 60 psi
idle hot 40 psi

Did two 10 min idle warm up cycles no issues.

Weather changed and I was able to drive it today
2500-3000k 70 psi
around 1k 40ish psi

after about a mile which included stopping shifting rpms ranging from idle to 3k (under 50 mph and under 35% throttle) I stopped as I noticed I lost a tool in the road. It sat and idled for about 5 mins.
when I got back my check oil warning was on and it was at 7.8 psi! I drove it down my long driveway around 1200 rpm and it never changed.
No noises, gave it a little rev when I parked it (1500 rpm) and still 7.8.

When I looked back at the data log @2700 rpm I had 72 psi
Later @2700 it had 45 psi

Idle went down to 12 psi

Running 5w30 valvoline for the break in with a wix filter. Any ideas?
Who ported the oil pump?

single or double row chain?


Last edited by KT35; 02-26-2020 at 01:11 PM. Reason: spelling
Old 02-26-2020, 01:24 PM
  #11  
TECH Fanatic
iTrader: (2)
 
WE TODD DID's Avatar
 
Join Date: Feb 2007
Posts: 1,627
Received 289 Likes on 169 Posts

Default

Originally Posted by ffjosh
Been searching but any way to test the oil sender unit? Ohms test I would guess
Put a mechanical gauge on it and check.
The following users liked this post:
TTur1996 (04-11-2020)
Old 04-10-2020, 05:28 PM
  #12  
Staging Lane
Thread Starter
 
ffjosh's Avatar
 
Join Date: Mar 2011
Posts: 68
Received 4 Likes on 4 Posts

Default

Put the oil sender on another car and read fine
pulled the engine and found silicone on the screen.

Mjust of came loose after I drove it
Old 04-11-2020, 08:16 PM
  #13  
Staging Lane
Thread Starter
 
ffjosh's Avatar
 
Join Date: Mar 2011
Posts: 68
Received 4 Likes on 4 Posts

Default

I lied oil pump relief valve was stuck (not due to debri) fixed it but I'm changing out all my bearings. One was a little sketchy



Quick Reply: Oil pressure random drop



All times are GMT -5. The time now is 02:40 AM.