Warning: If the low oil pressure warning light comes on while the engine is running and continues to light at high speed, this is an alarming sign. You must immediately stop driving, stop the engine and find out the cause of the malfunction. Further operation of the engine with low oil pressure can lead to serious damage and large financial costs for repairs.
Checking the lubrication system
1. Open the hood. Do not rush to check the oil level in the engine right away, let it drain into the oil pan, this will take two to three minutes. During this time, carefully inspect the engine - are there any fresh oil leaks on it.
2. Look under the front of the car to see if the engine oil pan is punctured or if there is a leak.
3. Pay attention to the oil filter. Oil may leak from under the rubber filter gasket if it is damaged or the filter is not tightened properly. Sometimes it is enough to turn it a little clockwise.
4. Remove the dipstick, wipe it with a clean cloth and reinsert it.
5. Remove the dipstick again and check the oil level. It should be between the "MIN" and "MAX" marks.
6. If the oil level is below the "MIN" mark, add oil to the level.
Helpful Hint: If you don't have a funnel for adding oil, you can use a funnel made from the neck of a plastic bottle.
7. Start the engine. If the oil pressure warning light goes out at a normal level, you can continue driving. If the light does not go out, check the oil pressure sensor. The sensor is installed at the bottom of the rear part of the cylinder block, next to the crankshaft pulley. Unscrew the standard oil pressure sensor and install a mechanical pressure gauge in its place. If the pressure at normal idle speed is more than 0.1 MPa (1.0 kgf/cm²) and increases with increasing rotation speed, the sensor or its electrical circuit is faulty.
Helpful Hint: If you don't have a pressure gauge, all you can do is check the reliability of the contact in the block with the sensor wires or replace the sensor with a known good one.
If after eliminating all visible causes the oil pressure in the engine is insufficient (the oil pressure warning light is on), perform engine diagnostics and repair.
Warning: Do not attempt to drive to a garage - the engine will fail. Have the car towed for repairs with the engine inoperative.
Helpful Hint: Before you begin repairing the engine, check the condition of the oil pump (see "Oil pump repair").
(The article was borrowed from the website «ChevyMan.ru»)