Nissan Altima 2007-2012 Service Manual: Compression pressure

On-Vehicle Service

CHECKING COMPRESSION PRESSURE

1. Run the engine until it reaches normal operating temperature.

2. Turn the ignition switch to OFF.

3. Release fuel pressure and leave the fuel pump electrically disconnected.

Refer to EC-1579, "Inspection".

4. Remove all six spark plugs.

Refer to EM-119, "Removal and Installation".

5. Attach a compression tester to No. 1 cylinder.

6. Depress accelerator pedal fully to keep the electric throttle control actuator butterfly-valve wide open to maximize air intake flow.

7. Crank the engine and record the highest gauge indication

8. Repeat the measurement on each cylinder (steps 5 - 7).

• Always use a fully-charged battery to obtain specified engine speed.


9. If compression in one or more cylinders is low:


9. If compression in one or more cylinders is low: a. Pour a small amount of engine oil into cylinders through the spark plug holes.

b. Retest compression (steps 5 - 8).

• If adding oil helps raise compression pressure, then the piston rings may be worn or damaged. If so, replace piston rings after checking piston.

• If the pressure stays low, a valve may be sticking or is seating improperly. Inspect and repair the valve and/or valve seat. Refer to EM-229, "Camshaft". If the valve and/or valve seat is damaged excessively, replace as necessary.

• If compression stays low in two or more cylinders that are next to each other: - The cylinder head gasket may be leaking.

- Both cylinders may have valve component damage. Inspect and repair as necessary.

    Camshaft valve clearance
    Valve Clearance CHECKING • Perform inspection as follows after removal, installation or replacement of camshaft or valve related parts, or if there is unusual engine conditions regarding valv ...

    Other materials:

    Tire pressure
    Tire Pressure Monitoring System (TPMS) This vehicle is equipped with the Tire Pressure Monitoring System (TPMS). It monitors tire pressure of all tires except the spare. When the low tire pressure warning light is lit and the “Tire Pressure Low - Add Air” warning appears in the vehicle i ...

    Rear window glass
    Components - Sedan 1. Rear window glass 2. Spacer 3. Adhesive 4. Roof panel outer 5. Rear window molding 6. Body side outer 7. Parcel shelf 8. Primer D. 7 (0.28) E. 12 (0.47) F. 12.5 (0.49) G. 16 (0.63) Components - Coupe 1. Rear window glass 2. Spacer 3. Adhesive 4. Roof panel ...

    AMP on signal circuit
    Description When the audio system is turned on, a voltage signal is supplied from the audio unit to the BOSE speaker amp. When this signal is received, the BOSE speaker amp. will turn on. Diagnosis Procedure 1.CHECK AMP ON SIGNAL (BOSE SPEAKER AMP) 1. Turn audio system ON. 2. Check voltag ...