Checking oil pressure (Chevrolet Trailblazer 1)

1. A decrease in the operating oil pressure in the engine may indicate the need for a major overhaul. The oil pressure warning light is not a diagnostic indicator for the lubrication system. It is activated when the oil pressure drops unexpectedly. Although the pressure indicator installed in the instrument panel has some error in readings, it is more informative than the emergency indicator. The most accurate readings can be obtained by measuring oil pressure mechanically (not electric) pressure gauge. Measure the oil pressure using an accurate tachometer and compare the results with the specification value for the relevant vehicle model.

2. Locate the oil pressure sensor located in the engine compartment (see illustration).



3. Unscrew the oil pressure sensor and connect the hose of a portable pressure gauge to the hole. Use an adapter if necessary. Wrap the threads of the connector/adapter with Teflon tape to seal the connection.

4. Connect an accurate portable tachometer to the engine, following its instructions for use.

5. Check the operating oil pressure in the engine lubrication system (at normal operating temperature) at the speeds specified in the specifications. Compare the obtained values with the values specified by the technical requirements. A significantly reduced pressure indicates possible wear of the engine bearings or oil pump.