Low/No Oil pressure help

[ericismyname]

Okay i had an earlier post about my oil pressure gauge being broken, well i have had the car for about 2 months now and the oil pressure gauge has not been working it remained all the way to the left. Now this morning i have oil pressure and the i am getting readings. However it does not even go up half way. It goes up the first line out of the 2 that makr the "ok" zone. But when i brake and slow down or coast the oil pressure goes down and then goes back up when i accelerate. This has only happened today on me. All the other time ive had the car it has always read nothing. im not sure what to replace other then the sender and oil pump. any help is appreciated. Thanks

 

[Enigma_Man]

It's probably the oil pressure sensor. On mine, the sensor connection came loose once, and it has read differently since I put it back on (it reads a little lower now, I think it's just not quite as good a connection as it was before).

I don't remember if the 90's have slightly different Oil filter housings... But on my 92, It's right in front of the driver side wheel well underneath the car. There's something that looks like a sideways bell with a little head on top of it. The head has a connector that slips over the side of it. Yours may be loose (I've been told that they often come loose on 1Gs), and just worked its way back on.

The engine wouldn't last 2 minutes w/o oil pressure (I know from experience). So you definitely have pressure, it's just not reading correctly.

-Jesse

 

[ericismyname]

allright i will fiddle with the connections to make sure they are all in tact and conencted fully tommarow night. Ill let you know results.

 

[laserblue]

The facts, mam.. only the facts! {That quote is from "Dragnet".}

The oil pressure gauge is a fairly simple device. When electricity flows thru it [nichrome wire is in there, like a toaster] a 'bimetal' strip heats up and the strip bends. It is connected to the needle which then also moves. Yours probably works although the needle and bimetal may be aging so it doesn't move enough.
The sender unit is known to make trouble in older cars. It could not be allowing enough current to flow thru, which makes the gauge read low.
The connector at the bottom of the sender unit could be crudded up or loose, so again - not good electrical flow.
This is what I did to test my gauge: I grounded the wire [at the sender unit] to the nearest metal while a friend [or enemy if you're like me] watched the gauge. If the gauge and wiring are good, the needle will pin full scale.
In the owner's manual it says... at idle the needle should move a tad but will still be over to the left. At 3000 rpms the needle should be approximately 1/2 way

.

So, that is what I learned by screwing around with my oil gauge. I hope the info helps!​

 

[ericismyname]

Thanks, this info does help out alot.

 

[cait sith]

I honestly, honestly suggest you throw out all the factory sensors and get a real oil pressure gauge while you're down there.

You don't have to spend 260 like I did on a 60mm P/H/W Greddy, but the stock oil pressure gauge is trash, on all generations. When you actually get the psi/bar readings in front of your face, it'll tell you that much more.

Considering my car has pushes upwards of 6.5 bar [that's over 87 psi] (And more when not so warmed up), and didn't move at all over "mid to 2/5th's" the way up, it's crap.

I lost my engine to no oil pressure. Not fun.