No/Low Oil Pressure
Instructor
Joined: Nov 2010
Posts: 151
Likes: 2
From: Lake Placid Florida
oil pressure relief valve
If the engine is fitted with an oil pressure relief valve - I'm not sure if the LS-series engines have these - debris may be holding the valve partially open so that it doesn't fully seat. Thus, at idle when oil volume and pressure are lower, this can bleed off pressure. At higher rpm, the 'leak rate' is a smaller percentage of the total oil flow so the pressures are normal.
Most oil filter have pressure relief valves to protect them for seal valve with overpressure at a cold start. A new filter may solve the problem. If the engine has a pressure relief valve, disassembly for cleaning would likely show the debris and allow for cleaning...End of problem.
Hope this helps.
PL Brand
Most oil filter have pressure relief valves to protect them for seal valve with overpressure at a cold start. A new filter may solve the problem. If the engine has a pressure relief valve, disassembly for cleaning would likely show the debris and allow for cleaning...End of problem.
Hope this helps.
PL Brand
Racer
Joined: Mar 2009
Posts: 447
Likes: 0
From: Adkins Texas
Yesterday on the way to lunch I noticed my idle oil pressure was ~15#. When I rev it up the pressure builds to ~40#. When I came out and started it there was ZERO pressure for ~10 seconds after the gauges were zone sweeping. 
After that it went back to the same low idle pressure.
When I went to go home it was similar. Zero for ~10 seconds, then up to ~30# until it started to warm up, then down to ~15# at idle. Oddly, about halfway home the idle pressure started to act normal again, staying ~25-30#.
I just changed the oil on Sunday and used Penzoil Premium synthetic 10W-30 and a Mobile 1 oil filter. Both unknowns as my standard is Mobile 1 5w-30 and Purolator Pure One or Fram ExtraGuard filter.
From my research here and on LS1Tech these symptoms have stemmed from anything from oil and filter to oil pump to cam and/or main/rod bearings. First thing I'm going to try is to change the filter, then the oil. It seems unlikely either would cause this, particularly the oil, but it's cheap enough to give it a shot before I yank the the rack and whatever else I need to in order to replace the oil pump which seems like the next likely culpret.
Thoughts? Comments?
After that it went back to the same low idle pressure.When I went to go home it was similar. Zero for ~10 seconds, then up to ~30# until it started to warm up, then down to ~15# at idle. Oddly, about halfway home the idle pressure started to act normal again, staying ~25-30#.
I just changed the oil on Sunday and used Penzoil Premium synthetic 10W-30 and a Mobile 1 oil filter. Both unknowns as my standard is Mobile 1 5w-30 and Purolator Pure One or Fram ExtraGuard filter.
From my research here and on LS1Tech these symptoms have stemmed from anything from oil and filter to oil pump to cam and/or main/rod bearings. First thing I'm going to try is to change the filter, then the oil. It seems unlikely either would cause this, particularly the oil, but it's cheap enough to give it a shot before I yank the the rack and whatever else I need to in order to replace the oil pump which seems like the next likely culpret.
Thoughts? Comments?
PM sent............
Thread Starter
Le Mans Master
Joined: Aug 2002
Posts: 8,472
Likes: 38
From: Houston TX
St. Jude Donor '11
FYI I had this problem come back, worse. Turned out to be the oil pressure relief valve stuck open.
http://forums.corvetteforum.com/c6-t...-pressure.html
The filter "fixing" the issue was just a coincidence. If you have a zero oil pressure problem I suggest rapping on the front cover or balancer with a rubber mallot. That will likely un-stick the valve at least temporarily.
http://forums.corvetteforum.com/c6-t...-pressure.html
The filter "fixing" the issue was just a coincidence. If you have a zero oil pressure problem I suggest rapping on the front cover or balancer with a rubber mallot. That will likely un-stick the valve at least temporarily.
