Engine finally got started!! But why oil pressure gauge don't move at all
 

Hi guys,

This is a exciting momoent... The engine finally starts after being parked for three years.......It idles well, it revs up well.....

However, i find the oil pressure gauge does not move at all....I remember when the car was running, the oil pressure gauge is always so responsive to the throttle... but now it is not moving at all, it's dead....

I check dip stick, there is oil in engine.

I let the engine idle about 5 mins. The water temp gauge goes up slowly, which is normal...

Also the fuel level gauge doesn't move at all, I have about 3 gallons in the tank. Weird thing is after I add gas into the tank the empty light is off but the level does not move at all.

Back to the oil pressure gauge... Any cheap way to tell if it is the gauge, the pressure sensor or it is really losing pressure.....To me if you would lose pressure at least the gauge moves a little bit, but now it is not moving at all...

http://forums.pelicanparts.com/uploa...1445095249.jpg

Have you tried 'tapping' the area in front of the oil gauge? My 951 does this sometimes on startup.

1. First, make sure that your gauge is lying. if you really do not oil pressure, you may have done irreparable damage to the engine!!! Remove the oil-pressure sender and plumb in a mechanicall oil-pressure test gauge. Start the car and see if you actually have pressure. If not, try the usual tricks, prime the pump through oil-filter hole. Check tightness of crank pulley, etc.

2. If you DO have oil pressure on stsrtup, then the gauge is not working. Check for continuity between both ends of the wires going to the oil-pressure sender. If wires sre OK, test the sender.

Hi,

I looks like your oil warning light is off. It is located just below the pressure gauge. Does it come on when the ignition is turned on before the car is started? If it does all is good and you have oil pressure, at least enough for idle.

If the light never comes on, I'd look for the missed wire or a bad bulb. You can just short the wires at the pressure sender to ground and the oil light should come on.

The gauge staying so low kind of suggests a short to ground, a sensor problem, or instrument panel problem. My gauge moves off of the stop, where yours is, to zero when the ignition is turned on.

Anyway, I'd see if the warning light is working first, them go at the sensor with an ohm meter......

Peter

Thanks Peter. I just checked. When the key is turned on before car is started, the oil pressure light is ON. Maybe the gauge is stuck. Same thing with my fuel level gage. I have fuel in the tank, I don't have the red light, but the level gauge stays at the bottom, it just don't move.

Good news that you have oil pressure!

Is your voltmeter reading zero too? I can't tell for sure from the picture. The oil pressure gauge and the voltmeter share a ground wire out of the panel (pin 8, plug C, Brown/yellow wire) to a multi wire crimp connection and then to the MP II inside firewall electronic ground. A problem with this connection would cause the volt meter and oil pressure to not work.

MP II is the brown wire bolted to the car body inside kind of under the central fuse/relay box. Follow back to find the multi wire crimp connections.

I would assume that you have a good 12 volt supply to the voltmeter and the oil pressure gauge as they share their power connection with the low oil pressure light bulb.

I don't have any ideas for your fuel gauge. It shares a ground wire with the the water temperature gauge (also to MP II through the same multi wire crimp as above). So I would assume that connection to ground is okay.

The fuel light warning warning bulb doesn't turn on unless the fuel level is low. There is no pre-start bulb check. (At least on my car...)

Peter

Two other thoughts....

If the voltmeter is working, I would look for a short to ground on the blue/white wire going to the pressure sensor. This wire has a long path around the front of the engine with many places to get damaged.

If the wire is good and your gauge is working, disconnecting the blue/white wire at the oil pressure sender should cause the gauge to peg over 5 bar when the ignition is on.


Peter

Yuma : any update?
Was Peteb correct about the ground wires?

I had a full scale oil pressure issue. The low pressure warning light wouldn't come on either. When I shorted out the gauge wire, the gauge went to zero. So, I bought a new VDO oil pressure sender because the aftermarket ones have a bad reliability history. Now I have proper pressure and the Low Oil Pressure warning light comes on when the ignition key is turned to run without the engine running. All Good.