That might be your knock sensor.
http://www.autozone.com/servlet/UiBroker/?UseCase=C001&UserAction=performSearch&Parameters=Auto+Store%7C%7ECOMPONENT+LOCATIONS%7C%7EOIL+SENDING+UNIT On your 1990 TOYOTA COROLLA, the OIL SENDING UNIT is: UNDER HOOD, PASSENGER SIDE, FRONT ENGINE AREA, MOUNTED ON UPPER PASSENGER SIDE OF CYLINDER HEAD
1999 Galant 2.4 SOHC - Oil pressure sensor (Oil Pressure sending unit) is located at the rear of the engine block, closer to the battery. The wire harness from generator has a short branch to the oil pressure sending unit. If you remove the battery and remove the battery base plate (three 12mm + two 10mm), you can reach the oil pressure sending unit. I have Haynes manual for Galant but Haynes manual says that oil pressure sending unit for 1999 Galant 2.4 SOHC is located in front of the engine near timing belt, but its wrong information. To replace, first pull out the slip connector. In my case, slip connector was loose when pulled out from the sensor. Prior to install slip connector, I had to remove plastic housing of the slip connector and tighten the slip connector with plyer. Remove the sensor using 1inch deep socket. If the sensor is rusted, it is recommended to apply WD-40 before removing the sensor (If you break the sensor, it must be very hard work to remove the thread and clean the cylinder!) You should apply liquid sealant on the sensor thread to prevent oil leakage.
The 1997 Dodge Dakota oil sending unit is in the oil pan, on the bottom of the engine. You will need to remove the oil pan in order to view the sending unit.
We need to know what sending unit you are asking about, there are several.
The fuel sending unit for the fuel gauge would be located in the fuel tank.
The oil pressure sending unit is mounted to the oil filter housing on the back of the engine. If you look up from under the car at where the oil filter is there is a wire connector that attaches to a piece on the side of where you screw the filter on. That is the oil pressure sending unit.
Your fuel sending unit is in the gas tank, mounted from the top.
It is usually on the top of the fuel tank, or close to it.
To the right of the Coolant temperature sensor. It has 1 wire connector
Bad connection at wireing connector at the oil sending unit. Bad sending unit. Replace as needed.
Any fuel sending unit I've ever seen is mounted into the fuel tank.
Mounted on top and inside the fuel tank.
Yes, It is mounted on the fuel sending unit inside of the fuel tank.
It is mounted on the fuel sending unit that is INSIDE of the fuel tank.
Mounted next to the oil filter.
temperature guage sending unit
May be mounted to or above oil filter