Hello - 2007 Yukon Denali 6.2 - 170,000 mi. Read many Low Oil Pressure posts. Seems like most say to replace oil pump o-ring, but symptoms in those posts say oil pressure is worse when cold, better when war/hot, due to cold seal not sealing as well, warm one seals better.
My symptom is backwards. Problem seemed to happen overnight. On 300-mile trip during Thanksgiving 2016, pulled-off half-way at a Wendy's, and engine shut off when getting in drive-thru. Started up in about a minute. Noticed idle pressure was less than 10. At destination, pulled up to son's driveway, engine quit.
Kind of repeat same thing coming back home. Engine will quit if left at lo-lo idle for very long - I guess a computer is shutting it down to protect it ?
Oh - as long as I'm stepping on gas, pressure is 40+, and everything runs great...but lift up foot quickly, and lo pressure quickly occurs...and sometimes engine quits.
Took to my usual car fixit place. They suspect main bearings and other wear/tear, and want to replace engine. Well, hold on there. There's also a small oil leak coming from way above the oil drain plug area, up above that - plug is on right-rear-corner of pan. Fixit guy says that is coming from small leak at 2 places on rear main seal...I can believe that. He also says that seal is not under pressure, so that fixing that seal won't help pressure. Is that true ?
(He has run the engine a couple of times to verify where oil is dropping from, and he took a picture of where oil drops landed on cardboard and I've seen the leak in my son's street, and my driveway before taking to fixit guy - so his and my seeing of where the leak is lines up.)
He has run engine from cold, just left idling to see what the pressure does. Started out at 40+, after 12-15 min's, needle moved to 30, 20, 10, and a little less...engine did not shut off. So like I said, bad o-ring in posts seem to say opposite direction. I'm wondering if mine just happens to seal better cold, and not when warm.
Any ideas ? I've posted here before, but been a couple of years and can't find USERIDPass, so I am now YD2007.
PS Mar 2016 oil sensor unit replaced by same fixit guy, and oil pan seal.
(and still Dave)
My symptom is backwards. Problem seemed to happen overnight. On 300-mile trip during Thanksgiving 2016, pulled-off half-way at a Wendy's, and engine shut off when getting in drive-thru. Started up in about a minute. Noticed idle pressure was less than 10. At destination, pulled up to son's driveway, engine quit.
Kind of repeat same thing coming back home. Engine will quit if left at lo-lo idle for very long - I guess a computer is shutting it down to protect it ?
Oh - as long as I'm stepping on gas, pressure is 40+, and everything runs great...but lift up foot quickly, and lo pressure quickly occurs...and sometimes engine quits.
Took to my usual car fixit place. They suspect main bearings and other wear/tear, and want to replace engine. Well, hold on there. There's also a small oil leak coming from way above the oil drain plug area, up above that - plug is on right-rear-corner of pan. Fixit guy says that is coming from small leak at 2 places on rear main seal...I can believe that. He also says that seal is not under pressure, so that fixing that seal won't help pressure. Is that true ?
(He has run the engine a couple of times to verify where oil is dropping from, and he took a picture of where oil drops landed on cardboard and I've seen the leak in my son's street, and my driveway before taking to fixit guy - so his and my seeing of where the leak is lines up.)
He has run engine from cold, just left idling to see what the pressure does. Started out at 40+, after 12-15 min's, needle moved to 30, 20, 10, and a little less...engine did not shut off. So like I said, bad o-ring in posts seem to say opposite direction. I'm wondering if mine just happens to seal better cold, and not when warm.
Any ideas ? I've posted here before, but been a couple of years and can't find USERIDPass, so I am now YD2007.
PS Mar 2016 oil sensor unit replaced by same fixit guy, and oil pan seal.
(and still Dave)
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