Chevrolet Sonic Repair Manual: Camshaft Intake and Exhaust Sprocket Replacement

Special Tools

EN-955-A Locking Pin

For equivalent regional tools, refer to Special Tools.

Removal Procedure

1. Remove the air cleaner assembly. Refer to Air Cleaner Assembly Replacement.
2. Remove the camshaft cover. Refer to Camshaft Cover Replacement.
3. Remove both camshaft position actuator solenoid valves. Refer to Camshaft Position Actuator Solenoid Valve Replacement.
4. Adjust the engine to TDC. Refer to Camshaft Timing Chain Adjustment.



5. Remove the timing chain tensioner plug (1) from the engine front cover.


6. Install a wrench (1) on the cast hexagonal portion of the intake camshaft, rotate the camshaft toward the exhaust camshaft in order to apply tension.


7. Install EN-955-A  pin (2) to the timing chain tensioner bore (1) to secure it in place.
8. Remove the wrench from intake camshaft.


9. Remove the upper timing chain guide bolts (1).
10. Remove the upper timing chain guide (2).
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11. Loosen the intake camshaft sprocket bolt (2) while holding up the hexagon of the intake camshaft with a wrench (1).
12. Loosen the exhaust camshaft sprocket bolt while holding up the hexagon of the exhaust camshaft with a wrench.


13. Remove and DISCARD the camshaft sprocket bolts (2) and the camshaft position exciter wheels (1).


14. Remove the camshaft sprockets (2) and timing chain (1) as one unit.
15. Remove the intake and exhaust camshaft sprocket.
16. Allow the chain to rest on the front cover.

Installation Procedure

1. Install the camshaft sprockets (2) and timing chain (1) as one unit.


2. Install the camshaft position exciter wheels (1).
3. Install the NEW camshaft sprocket bolts (2) hand tight only.
4. Remove the EN-955-A  pin to apply tension to the timing chain .

Note:

Engine must be adjusted to TDC.

5. Adjust the camshaft timing chain. Refer to Camshaft Timing Chain Adjustment.



6. Install the upper timing chain guide (2).

Caution:

Refer to Fastener Caution.

7. Install the upper timing chain guide bolts (1) and tighten to 8 Y (71 lb in)

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8. Install the timing chain tensioner plug (1) and tighten to 50 Y (37 lb ft)

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9. Install both camshaft position actuator solenoid valves. Refer to Camshaft Position Actuator Solenoid Valve Replacement.
10. Install the camshaft cover. Refer to Camshaft Cover Replacement.
11. Install the air cleaner assembly. Refer to Air Cleaner Assembly Replacement.
12. Check and correct engine oil level.