96 Z28 idle and oil pressure
03-12-2011, 08:20 AM
#16
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Location: St.louis
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Re: 96 Z28 idle and oil pressure
if oil pressure seems low to you guys..i hate to see what 80-90psi seems to you guys
6 psi for 800rpm is gm manufacture specs..anything over is a bonus..
if oil psi increases with rpm then you are fine...if oil does not then you have other issues.
put a real gauge on it and varify..most factory gauges read 3-5 psi low or high..
6 psi for 800rpm is gm manufacture specs..anything over is a bonus..
if oil psi increases with rpm then you are fine...if oil does not then you have other issues.
put a real gauge on it and varify..most factory gauges read 3-5 psi low or high..
03-13-2011, 05:44 AM
#18
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Location: from Arkansas now in tennessee
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Re: 96 Z28 idle and oil pressure
i just got the oil and filter valvoline 5w30 and wix filter and a new fuel filter i plan to change later today i smelled the oil on the dipstick it was fine but i will get a better tell when i drain it and i have herd 6 psi normal on a lot of sites just sounds low . there is no abnormal engine noise . the coment on the tps or iac or map sensor was more tords the rpm bottoming out and sometimes dies when i put it in park or drive but sometimes it stableizes back to 800. and about what psi would be the red on oil pressure gauge. i also plan to change tranny fluid and filter on thursday if it doesnt rain.
03-13-2011, 09:41 AM
#19
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Re: 96 Z28 idle and oil pressure
Never hurts to read the Owner's Manual:
The light "Check Gages" light comes on at 6psi.
Engine Oil Pressure Gage
This gage tells you if there could be a problem with your
engine oil pressure.
The engine oil pressure gage shows the engine oil
pressure in psi (pounds per square inch) in the United
States, or kPa (kilopascals) in Canada, when the engine
is running. Oil pressure should be 20 to 80 psi (140 to
550 kPa). On the 3.8L engine, the oil pressure should be
between 20 and 120 psi (140 to 827 kPa). It may vary
with engine speed, outside temperature and oil viscosity,
but readings above the red area show the normal
operating range. Readings in the red area tell you that
the engine is low on oil, or that you might have some
other oil problem. See “Engine Oil” in the Index.
This gage tells you if there could be a problem with your
engine oil pressure.
The engine oil pressure gage shows the engine oil
pressure in psi (pounds per square inch) in the United
States, or kPa (kilopascals) in Canada, when the engine
is running. Oil pressure should be 20 to 80 psi (140 to
550 kPa). On the 3.8L engine, the oil pressure should be
between 20 and 120 psi (140 to 827 kPa). It may vary
with engine speed, outside temperature and oil viscosity,
but readings above the red area show the normal
operating range. Readings in the red area tell you that
the engine is low on oil, or that you might have some
other oil problem. See “Engine Oil” in the Index.
03-13-2011, 07:02 PM
#20
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Location: from Arkansas now in tennessee
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Re: 96 Z28 idle and oil pressure
i just change the oil it did not have a fuel or coolant smell but did not smell or feel like conventional oil i think it might have been royal purple but black. the tranny was over full but looked fresh so i sifond out almost half a gallon of royal purple trans fluid now it is at the full mark when at operating temp i think i gained a few psi after oil change about 10 psi when worm at 800 and 20 at 1000. thanks for the quote i dont have an ouners manual got the car used . iplan to replace the sending unit thursday if not raining if it doesnt improove i will have to break down and take to a real mechanic if it is bad bearing i will probably have to sell it i cant afford a couple of grand toget rebuilt and dont have the tools or experience to do that one myself.
03-16-2011, 04:36 PM
#21
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Join Date: Dec 2010
Location: Oahu, HI
Posts: 388
Re: 96 Z28 idle and oil pressure
i just change the oil it did not have a fuel or coolant smell but did not smell or feel like conventional oil i think it might have been royal purple but black. the tranny was over full but looked fresh so i sifond out almost half a gallon of royal purple trans fluid now it is at the full mark when at operating temp i think i gained a few psi after oil change about 10 psi when worm at 800 and 20 at 1000. thanks for the quote i dont have an ouners manual got the car used . iplan to replace the sending unit thursday if not raining if it doesnt improove i will have to break down and take to a real mechanic if it is bad bearing i will probably have to sell it i cant afford a couple of grand toget rebuilt and dont have the tools or experience to do that one myself.
03-19-2011, 09:10 PM
#23
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Location: from Arkansas now in tennessee
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Re: 96 Z28 idle and oil pressure
i found a coolant line on the throttle body was penched at a 90 degree angle and spung a leak and was spraying on the throttle position sensor and i just got my hands on a code reader i got 6 codes one of which was the tps that might be part of the problem also keep getting maf sensor malf but i just replaced it (not cheap) the codes were P0100, P0121, P0300, P0412, P01641, and P01642. i dont know were to start i know sometimes you can have 1 problem to throw multiple systems out of wack
03-19-2011, 09:44 PM
#24
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Re: 96 Z28 idle and oil pressure
P0100 indicates the MAF sensor reading is static. If you are sure the MAF sensor is OK, it may be a failure in the wire harness. Key on/engine off, pull the harness connector off the MAF sensor, and measure the voltage between the pink wire (12V power supply to MAF) and the black/white (ground) wire. Should read 12V.
P0121 indicates static TPS sensor reading. Again, check for 5V across the gray wire (5V power supply) and the black wire (ground). If you have 5V, check the voltage between the green wire (signal) and the black wire. Should be between 0.20-0.90V at closed throttle (with 0.65V being a typical stock reading) and should increase smoothly by about 4V as you slowly open the blades.
P0300 is random misfire, the result of the other problems, or coolant on the ignition system components.
P0412 is AIR pump voltage problem. Could be a blown fuse, or faulty relay for the AIR pump (or shorted from coolant).
P1641 (there is no P01641) is Primary cooling fan relay circuit malfunction, and P1642 is Secondary coolibg fan relay circuit malfunction.
Appears the coolant spraying all over the front of the engine has shorted out the wiring connections.
P0121 indicates static TPS sensor reading. Again, check for 5V across the gray wire (5V power supply) and the black wire (ground). If you have 5V, check the voltage between the green wire (signal) and the black wire. Should be between 0.20-0.90V at closed throttle (with 0.65V being a typical stock reading) and should increase smoothly by about 4V as you slowly open the blades.
P0300 is random misfire, the result of the other problems, or coolant on the ignition system components.
P0412 is AIR pump voltage problem. Could be a blown fuse, or faulty relay for the AIR pump (or shorted from coolant).
P1641 (there is no P01641) is Primary cooling fan relay circuit malfunction, and P1642 is Secondary coolibg fan relay circuit malfunction.
Appears the coolant spraying all over the front of the engine has shorted out the wiring connections.
02-04-2012, 06:32 PM
#25
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Join Date: Feb 2012
Posts: 2
Re: 96 Z28 idle and oil pressure
i have a 95 z28 with this same issue but when at idle after warm my temp starts going hot thinking gauges were messed up i let it go then the check gauge light came on and my car shut down and when fired back up acted like it was flooded this is my 1st lt1 it only has 117000 on it any advice with the issues would be great
04-09-2017, 01:01 AM
#26
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Join Date: Apr 2017
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Re: 96 Z28 idle and oil pressure
I have a 93 z28 6 speed. My idle is set around 750. On the tach it reads 950 - 1000. The tachs are usually off by 100 200 rpms. Anyway at 750rpms after I switched to a high velocity pump few months ago. Running temp it holds about 70pis 65 when cold. I have alot of performance parts tho
04-09-2017, 07:08 AM
#27
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Location: Kissimmee, Fl, USA
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Re: 96 Z28 idle and oil pressure
I have a 93 z28 6 speed. My idle is set around 750. On the tach it reads 950 - 1000. The tachs are usually off by 100 200 rpms. Anyway at 750rpms after I switched to a high velocity pump few months ago. Running temp it holds about 70pis 65 when cold. I have alot of performance parts tho
It looks like you're new to the site. Why not take a minute to fill out a signature. It helps everyone answer questions as/if they crop up. It's easy to do...go to User CP and you'll find it.
a quick point...oil pumps come in high volume or high pressure. I suspect you meant high pressure, not high velocity.
Take care,
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