Low oil pressure, WTF??
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Low oil pressure, WTF?? So I go to taco bell for some food and on the way back go WOT through first and second then afterwards my oil pressure gauge is reading low, like 25-30psi at idle. It usually sits at 40 at idle. It goes up to the 40 area up to 2500 rpm's then goes up a lot when the push the rpm's up. When Im cruising along and i push the gas it drops slightly and then goes back up when I come off the gas. Like when its loaded the pressure drops a bit.
First thing I did was change the oil/filter and pulled the valve covers off and had a look. Everything looked OK so I buttoned it up and drove the car a little bit. It sounds fine and isnt skipping a beat at all. No ticking or stange sounds. I am suspecting either a bad pressure sending unit/gauge or a slowly failing oil pump. I almost 99% sure its not a rod bearing or anything like that. Once I get a mechanical gauge on it I can narrow it down a little more.
What do you guys think? This **** pisses me off.
First thing I did was change the oil/filter and pulled the valve covers off and had a look. Everything looked OK so I buttoned it up and drove the car a little bit. It sounds fine and isnt skipping a beat at all. No ticking or stange sounds. I am suspecting either a bad pressure sending unit/gauge or a slowly failing oil pump. I almost 99% sure its not a rod bearing or anything like that. Once I get a mechanical gauge on it I can narrow it down a little more.
What do you guys think? This **** pisses me off.
Last edited by brad8266; Mar 5, 2008 at 05:29 PM.
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Well I chaged it 10 minutes after the pressure dropped. Changing it really didnt do anything for the pressure. It still gets enough at WOT it doesnt have pressure at low rpms's like it did before.
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what kind of oil, and filter you use? i notice my oil pressure drop when i used penzoil platinum, and k&n filter.. went back to mobil, and wix filter. my pressure is good now 
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hmmm.. only thing i can think of is maybe the oil pump is failing. i had that problem of it getting that low with my stock oil pump. at idle it would sit around the same psi u mentioned. i doubt yours is stock. so it seems wierd that you have this problem.
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Yeah its a ported LS6 pump. They still fail though sometimes. Im hoping its just the sender, that would be sweet.
When the oring or pump are a problem at work, you will hear some lifter noise. I would check the oil pressure with a manual guage? or swap the oil pressure sending unit with someone you know? When I have a oring problem Ive always had some noise.
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Yeah thats what i was thinking, I mean the motor sounds perfect. I have one of the most quiet head/cam ls1 cars I have heard and even with the low gauge it still sounds perfect. Thats why I am hoping its just the sender.
What weight oil are you running? Do have excessive clearance from stock on crank and rods?
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Thats what Im hoping. That will only cost me $20 and an hour of my time. Its juts weird that my readings are off as soon as I went WOT for a few seconds.