Replacing the UAZ oil pressure sensor

The oil pressure sensor in cars of the UAZ family regulates the level of lubrication of engine components and parts. Its principle of operation and functions are traditional: monitor the oil pressure in the system and give a signal in case of insufficient or excessive pressure. However, UAZ vehicles of various modifications and even the year of manufacture have a different permissible arrangement of oil pressure indicators and sensors.

The principle of operation and the main parameters of oil pressure sensors for UAZ vehicles

Oil pressure sensors for UAZ vehicles of various models and modifications differ markedly from each other. Therefore, the car owner must be very careful when replacing the sensor. The label of the new element must exactly match the information specified in the body of the previous failed element.

"Hunter"

The oil pressure sensor of the UAZ Hunter car is an AC resistor; its resistance will change with pressure. It is marked MM358 and has the following specifications:

• operating voltage - 12 V;
• maximum allowable oil pressure 6 kg/cm2;
• thread for M4 screw;
• at an oil pressure of 4,5 kg / cm2, the sensor resistance is from 51 to 70 ohms;
• works in combination with type pointer 15.3810.

This is how the oil pressure sensor of a UAZ Hunter car looks like

"Loaf"

The sensor on the UAZ "Loaf" car is marked 23.3829. Its technical characteristics and principle of operation are similar to the UAZ "Patriot" discussed above. One slight difference is that the working element is a rheostat, not a resistor.

It looks like an oil pressure sensor from a UAZ Loaf car

"Patriot"

The sensor of this UAZ model is marked as 2312.3819010. The principle of its operation is the same as that of Hunter and Loaf. The main element is a resistive device that is sensitive to changes in oil pressure in the system. It has the following characteristics:

• operating voltage - 12 V;
• maximum allowable oil pressure 10 kg/cm2;
• thread for M4 screw;
• at an oil pressure of 4,5 kg / cm2, the sensor resistance is from 51 to 70 ohms;
• works in combination with pointers of all kinds.

The oil pressure sensor of the UAZ "Patriot" car is similar to its predecessors

Sensor location

The sensor is located in the engine compartment of the UAZ vehicle. On the UAZ "Loaf" and "Hunter" models, it is installed directly on the engine above the exhaust manifold. On the UAZ "Patriot" it is located in the same place, but is closed with a protective casing from high temperature and steam emitted by the collector.

The sensor is mounted on the engine housing above the exhaust manifold.

Functional Testing

The technology for checking the performance of the oil pressure sensor on the UAZ Hunter and UAZ Loaf is almost identical, and on the UAZ Patriot a slightly different procedure is offered.

"Hunter" and "Loaf"

To diagnose the condition of the oil pressure sensor, do the following:

1. Disconnect the XP1 connector from the vehicle instrument panel.
2. Turn on the ignition.
3. Connect an additional wire to pin #9 and short it to the case. The oil pressure gauge on the dashboard should show 6,0 kg/cm2.
4. Throw an additional wire to contact No. 10. The indicator reading in the cabin should increase to 10 kg/cm2.

If the actual pressure value corresponds to the set values, then the sensor is OK. Otherwise, it must be replaced immediately.

"Patriot"

1. Disconnect terminal #9.
2. Turn on the ignition.
3. Connect terminal No. 9 to the ground of the XP1 unit.

A repairable element with a change in pressure should show the following values:

• at 0 kgf/cm2 - 290–330 Ohm;
• at 1,5 kgf/cm2 - 171–200 Ohm;
• at 4,5 kgf/cm2 - 51–79 Ohm;
• at 6 kgf / cm2 - 9,3–24,7 Ohm.

In case of discrepancy between the specified values, the device must be replaced.

Video: performance check with a pressure gauge

Replacement

The algorithm for replacing the oil pressure sensor on cars of the UAZ family is quite simple. You will need the following tools and supplies:

• fixed key at 17;
• fixed key at 22;
• screwdriver;
• sealant

The work is recommended to be performed in the following order.

1. The wires of the sensors, one of which is connected directly to your contact, and the other to the alarm device in the cabin, mark with multi-colored markers. Disconnect cables.
2. Unscrew the screw that secures the lug of the cable going to the device.
3. Remove the motor guard with a screwdriver. Disconnect the negative battery terminal with a wrench
4. Open the hood.
5. Using a 17 wrench, disconnect the negative battery terminal. Disconnect the two wires from the faulty oil pressure sensor
6. Using a 22 key, unscrew the old sensor.
7. Install a new element, after applying a little sealant to its threads.
8. Connect the previously marked cables to the new device.
9. To check the functionality of the new sensor, start the engine and after a while look for signs of oil leakage. If not, tighten all threaded connections further.

Therefore, the procedure for checking the performance and replacing a faulty oil pressure sensor on cars of the UAZ family is quite simple. When installing a new device, special attention should be paid to its labeling - different models use different elements. Good luck on the roads!