oil pressure drop once warmed up

blueyed tuner · 06-11-2012, 03:45 PM

Check the GM Bulletins on the make and model of the engine. At one time there was a bulletin out that stated GM had some pumps with faulty relief valves. You would start engine up cold with good pressure and as the engine warmed the relief valve would stick open, as the engine would cont to warm to operating temp the oil gets slightly thinner and if the relief doesn't close slightly at this temp you have low oil pressure. When the engine cools the relief unsticks and closes so when time for the next start up your oil pressure seems to be normal. It will drive you insane. May not be the problem, but something to check I guess. I will check and see if I can find the bulletin info.

06-11-2012, 03:45 PM	#30
blueyed tuner Senior Member Join Date: Nov 2011 Location: Summerville SC Posts: 214	Check the GM Bulletins on the make and model of the engine. At one time there was a bulletin out that stated GM had some pumps with faulty relief valves. You would start engine up cold with good pressure and as the engine warmed the relief valve would stick open, as the engine would cont to warm to operating temp the oil gets slightly thinner and if the relief doesn't close slightly at this temp you have low oil pressure. When the engine cools the relief unsticks and closes so when time for the next start up your oil pressure seems to be normal. It will drive you insane. May not be the problem, but something to check I guess. I will check and see if I can find the bulletin info. __________________