There is a open on the sender side of the circuit. Ground the sender wire and if it goes to low then it is the sender if not then the circuit is open.
Oil pressure has to built up. As long as the pressure is normal and the oil level is good. There is no problem.
i have a 1993 190E - my oil pressure gauge always sits on 3. ==New Answer Haedline == The oil pressure gauge actually moves but is related to several factors Engine Temprature Oil viscosity Engine speed. When you start you car the engine temperature is low the gauge goes to 3, after a long drive/travel and if your temp gets to 80C then with an engine speed of 750-800 RPM you oil pressure gauge will read about 1.5. if you rev. the engine the pressure gauge goes up to 3
Gauge Cluster Board Bad
Your oil pressure goes up with more throttle (higher rpm) and there is less pressure say at idle. Therefore your gauge reading will vary according to the throttle/rpm.
AnswerWhat do you mean by haywire? Without more information, all I can tell you to do right now is to replace the filter you are using with an AC/Delco filter. The oil pressure sending unit may be defective if you are getting erratic readings. I mean that the water temp gauge needle goes way past the point to where it bottoms out and so does the battery volt gauge needle and the oil pressure gauge needle and the tach needle works when it wants to.
You would need a gauge that taps into where sender goes on block.
oil gage pressure immediately goes high
Your car is starting to overheat or your thermostat is going out. Get it checked.
If you have the correct weight oil in the engine, it sounds like the engine may be worn. If you haven't checked the oil pressure with a manual gauge (vs the dash gauge) that is a good place to start to verify that it is not a gauge/sensor problem.
Hey Sim==If it does it only while the engine is running, the sending unit could be inacurate. You need to install a manual gauge to see what the actual reading is. If it goes to red before starting the engine the wire to the sending unit is probably disconnected. Good luckJoe
Waht is the answer?
the oil pressure sending unit is designed to warn you of a low oil pressure. If the sensor goes bad then the low pressure light or gauge will read low when the oil pressure is actually ok.