spyder24

Ok i have been reading a few posts regarding low oil pressure problems. but i figured i could maybe find a good answer if i explained my problem. I have a 96 z28 with 112k on it but the engine has around 60k on it. i had it put in about 4 months ago and only has been driven about 3k since..never had any real issues with the OP when i first got the car back. It sat for about 2 months over winter and before winter i changed the oil and put Royal Purple in. The engine is stock internally .. only cold air intake and magnaflow exaust on the car. Recenlty my car has been getting really low oil pressure after a few miles of driving during idle. While idling my RPMS stay around 600 rpms and the oil pressure dropss to the very bottom and the CHECK GAUGES light comes on. but when i rev it in neutral or am driving in gear it is fine. This is really bothering me and i dont want to ruin this motor considering i just got it put in. Like i siad i had no previous problems with this until recently all of a sudden. Everything seems fine other than that i am not hearing any knocking or ticking at all it gets up n goes when i want it to but it doesnt feel to good when it is idling. Read things such as oil pick up tube, sending unit, and other things along those lines.. if anyone has any idea were to look or what it could be would be great. thanks

MikeGyver

This happened to me and my motor spun a bearing the same night.
Replace your oil filter.

Injuneer

Check the oil for fuel dilution. If its running rich and fuel is bypassing the rings, its possible for the oil to thin enough to reduce pressure.

shoebox

The oil pressure sensor may be faullty. You might want to verify pressure with a mechanical gauge or replace the sensor.

spyder24

how do i check for fuel dilution?

87bandit

does your oil smell like gas pretty much

MTL_Z28

Well, when you change your oil if you smell a faint gas smell that might mean that there is in fact gasoline seeping through into your oil like injuneer was saying. But just because you can't smell anything when you change your oil it doesn't mean it's not hapenning...

The only way to know for sure would be to take a sample of your oil and send it off to be analysed. Blackstone labs is where I send my oil once per year.

I was actually having the same problem as you. After driving the car a while (say 15 mins) the oil pressure at idle would be lower than usual. So I sent my oil off and they found that about 2.5% of my oil sample was actually gas They told me not to worry though and that if you don't drive your car very often and only for short trips, it's normal that a little bit of gas accumulates in the crankcase. They told me next time to go on a very long highway run before taking the oil sample. Long drives tend to 'cook out' any gas that may be in the oil. I did that the following year and almost no gas in the oil sample (<1% which is normal).


If I were you I would definitely send them a sample, they can definitely give you lots of info just with one sample. They may even be able to tell you if a bearing was going out...

DAFAIC

Or the dash gauge is off like mine. It's off by 10psi on the low side. Factory minimum specs is 7psi at idle. So once my oil pressure drops to 10psi the arm on the gauge just drops and the check gauge lite comes on.

I replaced the sending unit and it didn't fix the issue.

I installed a 2 5/8" oil pressure gauge into the middle airvent above the radio. Looks sweet and I can always watch the pressure. If you have the same situation do not drive the car like that. You need an operational and properly functioning oil pressure gauge so install an oil pressure gauge. Oh and if you have the same problem I do replacing the cluster is not a guarantee fix either. Save your money and install a oil pressure guage.

Hell go by a cheap $10 from autozone throw it into the plug under the driver head and just check it. I ran a cheapo gauge and temp installed it under the radio with the little cup pulled out till I found the gauge I wanted and ordered it. This plugged hole is actually the location of the 93 LT1's oil pressure sending unit.

spyder24

ok im going to have it hooked up to a mechanical gauge or w.e eveyrone is talking about.. i recently changed the oil and filter and its doing it still.. but the thing im not getting is everyone is saying it could be my gauge. the thing thats killing me is if it was just the "gauge" wouldnt that mean the oil pressure could be fine just the "gauge" isnt showing the right reading? if thats the case then ok i will fix that if it is the problem but the thing i dont get is when the car does act like this i can tell the sound in the engine changes.. the RPM's drop down to almost 500 along with the oil pressure going down to almost nothing sometimes to nothing and the engine sounds like it wants to die. So what i wanna know is if i do fix the gauge or w.e and it is bad what will i want to check next? ive heard people thinkin it could be the oil pump.. pick up tube or what? id ont get it. i just want to know where to look and what to get to fix this.

87bandit

sounds more like problem with your motor holding an idle than oil pressure

oil pressure is reflected upon the rpm the motor is turning, if the car is barely holding an idle then of course oil pressure will be low. check gauges can be for any bad reading on any of the gauges

spyder24

ok so what could it be then? when it is in neutral it takes all that pressure off by the way. and it feels fine while driving just when i come to a stop while still in drive or anything but neutral.

SmokeyBlaZe

Its the pick up tube https://www.camaroz28.com/forums/sho...sure+acting+up

camaroz28383

step one should be checking it with a mechanical gauge
mine does the same thing when at idle when its hot in gear but have had no problems for 2 years
the stock gauges are pieces O crap

kasey079kahne

I have a similar problem and didnt see exactly what mine does on here so ill post and if it is sorry but please help me out if you can....i have a 1995 z28 that has 119k...i had head gasket fixd and mechanic said he fixd someother stuff as i bought the car after it sat for 2 yrs. but i drove it for almost 100 miles over 2 days and most was just geetin it home and it ran fine, but when coming home from friends ouse car didnt want to **** out of 2nd so i lifted out of gas and it then shifted. well then my check gauges came on(oil pressure was 0) and when i got to stop sign car stalled so i shut off everything and got it started back up and got home but at all other stops i held gas slightly while stopped and the oil pressure gauge continued to zero out when i wasnt in throttle at all. what is the cause of this? i checked oil the oil looks fine and has plenty. i tried to use a code reader and couldnt get a read just came up error. any help would be greatly appreciated Thanks.

Injuneer

kasey079kahne:

The best thing to do is to start your own thread, rather then interfere with someone else's. This is called thread hijacking.

There are two possibilites:

1 - The oil pressure sending unit/gauge is not working correctly. Check the oil pressure with a mechanical gauge, attached to the spare oil port right above the oil filter. Photo courtesy of Shoebox:

http://shbox.com/1/aux_oil_port.jpg

2 - If you get 0psi at idle, and some oil pressure as RPM goes up (what is the pressure at 2,000rpm for example?), its either a spun bearing or a damaged oil pump or pickup.