Oil pressure or guage issue?

mkiii 4 life

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Apr 25, 2008
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I have a stock 7m-gte and the oil guage goes up to a little over 20psi on the first startup of the day and as soon as it warms up it drops and sits on the bottom. The car can sit for 8 hours and it still wont move unil the next day first start up again. I am running royal purple 10w30 oil and the car has 103000 miles on it. Any ideas?

Thanks
 

HommerSimpson

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Dec 31, 2007
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mkiii 4 life;1106203 said:
I have a stock 7m-gte and the oil guage goes up to a little over 20psi on the first startup of the day and as soon as it warms up it drops and sits on the bottom. The car can sit for 8 hours and it still wont move unil the next day first start up again. I am running royal purple 10w30 oil and the car has 103000 miles on it. Any ideas?

Thanks

get a MANUAL GUAGE ASAP and see what exacly you pressure is..

what was it? when did this start ? how long you been driving like this ?
 

Rennat

5psi...? haha
Dec 6, 2005
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how do you even know its above 20psi??? none of the gauges i've ever seen are in psi... mine on a cold start goes up to the first line, and then when its warmed up after a start, its between that line and the bottom...

we have a high volume low pressure type of oil system... so remember that.
 

mkiii 4 life

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Apr 25, 2008
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South Florida
Rennat;1106263 said:
how do you even know its above 20psi??? none of the gauges i've ever seen are in psi... mine on a cold start goes up to the first line, and then when its warmed up after a start, its between that line and the bottom...

we have a high volume low pressure type of oil system... so remember that.

Yea mine goes a little above the first line on cold start up then stays at the bottom line.
 

Nick M

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Sep 9, 2005
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How long have you owned your car? As the engine bearings wear, their clearance becomes bigger.

That lowers resistance to flow, making the gage read lower resistance, aka psi.

As the engine ages, the spring that is the relief valve can soften, opening it earlier, reducing flow to the engine. And if less oil tries to displace a set confine, pressure will be lower, aka psi.
 

mkiii 4 life

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Apr 25, 2008
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South Florida
Nick M;1106278 said:
How long have you owned your car? As the engine bearings wear, their clearance becomes bigger.

That lowers resistance to flow, making the gage read lower resistance, aka psi.

As the engine ages, the spring that is the relief valve can soften, opening it earlier, reducing flow to the engine. And if less oil tries to displace a set confine, pressure will be lower, aka psi.

i have had the car for a year and have had BHG(about 10,000 miles ago)
 

Nick M

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Driving with an oil-coolant milkshake will not protect your engine bearings or crankshaft. "Rod knock" is often heard afterward by those that do.
 

jetjock

creepy-ass cracka
Jul 11, 2005
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Guess that "lb/in2" thing is confusing to some ;)

OP: There's no sense wondering what's going on unless you can trust the gage and the only way for that is to do what Hommer said. The stock gage is of a quirky design because it has to talk to the ECU and gives up some accuracy and response time in return. It can be made much more accurate but takes a bit of work. Since your engine hasn't blown up you must have sufficient pressure. Contrary to popular belief it doesn't need all that much. My stock gage has been carefully calibrated and I never see more than 30 psi in typical hot cruise, keeping in mind the oil I run is specifically selected to cause that.