crazy oil pressure---help
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From: North Carolina
crazy oil pressure---help I have an LS2 with a 4L60 out of an '06 GTO. It is in a classic car. Here's the problem. The oil pressure is fine when running at low rpm's, at around 40-45lbs. I have an electric gauge. The pressure will remain the same until I get to about 2000 rpm. (approx 60mph) At that point it drops to about 30-35psi. It isn't a slow drop, but an instant drop. I have replaced the gauge and sender with the same results. I have installed a mechanical gauge with the plastic tube and the same thing happens. The sender is mounted at the rear of the engine behind the intake manifold. The engine runs great with no problems or noises. The gauge will stay at the lower pressure reading until I slow down to around 1200rpm (approx 35mph) when it will jump back up again. When I'm going about 50mph and the reading is 40psi, if I drop it down to 3rd gear increasing the rpm, the pressure drops. It is definatly rpm/pressure related. Does anyone know if there is some kind of by pass valve in the oil pump that could cause this ? I have called everyone I can think of that might have an explanition, but no one has ever heard of this problem. This isn't an occasional thing. It happens every time I drive it. I thought it was some kind of electrical problem until I put the mechanical gauge in with the same results. I've talked with other people with the sender mounted where mine is and they have never had this problem. I'm frustrated to say the least. Any thoughts and/or suggestions would be most welcome and appreciated.
Tom
Tom
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From: Your GF's pants
There is a check valve in the oil pan to limit oil pressure. Might have crap in it, not allowing it to function properly when the pressure is supposed to come up. What kind of oil are you running?
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Ok well we need more opinions because I am not too experienced with the GTO 6.0. In the L76 in the G8 the check valve is located in the actual pan body next to the oil filter, and is to limit oil pressure from going over ~55PSI. I think its main function is for DoD applications though and I dunno if you have one. That oil is fine to be ran though...
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There may be a blockage in the screen/pickup tube though. Once I found a Canadian sticker in an engine's pickup tube, that I have no idea how it got there. Same issue though that you're having. 35PSI is not low enough to hurt anything though.
subscribing - I had an oil change done this afternoon but I'm having the opposite. On the drive home tonight the Oil pressure was about 100 and then dropped quickly back down to 60ish.
IDRIVEAG8GT - does your check valve idea apply to an Ls1 also? I noticed the oil change guy carrying something that looked like some sort of "key" in shape of a cd.
Is the check valve adjusted per oil change?
IDRIVEAG8GT - does your check valve idea apply to an Ls1 also? I noticed the oil change guy carrying something that looked like some sort of "key" in shape of a cd.
Is the check valve adjusted per oil change?
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Still have yet to figure that out on the pressure regulator. Sorry guys, I'm having a massive problem with a 427 stroker.... So research is a bit hard. Um.... Unit in the shape of a key?? Well if your car had it adjusted they'd have the pull the engine and drop the pan.... And I don't think that that is required in an Oil Change. 
Check and make sure that your sending unit is plugged in well. If they don't make good contact then they won't read accurately. After all, the sensors do work off of resistance. In your case though if that isn't it, then they probably put too thick of oil in it. Was it cold or warm?
Check and make sure that your sending unit is plugged in well. If they don't make good contact then they won't read accurately. After all, the sensors do work off of resistance. In your case though if that isn't it, then they probably put too thick of oil in it. Was it cold or warm? Trending Topics
In my case it does seem to be sending unit that may not be plugged in correctly.
The oil I use for winters is 5w-30 and I noticed the spike at normal warm temps while driving at 2k rpms.
The oil I use for winters is 5w-30 and I noticed the spike at normal warm temps while driving at 2k rpms.
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From: Your GF's pants
Hey does your car have a FRAM oil filter? Some FRAM's are notorious to just implode on the inside. I have had it happen twice to me, and now I run Mobile 1 Filters. No problems since.
