L322 Range Rover System Description and Operation
ENGINE MANAGEMENT SYSTEM – V8
18-2-48 DESCRIPTION AND OPERATION
VCC Timing Procedures
Always refer to the Service Procedures Workshop Manual for valve timing procedures. The V8 valve timing
adjustment requires the setting of the VCC transmissions to their maximum retard positions with an ohmmeter and
attaching the camshaft gears to each camshaft with single reverse threaded bolts.
The process is as follows:
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After locking the crankshaft at TDC, the camshaft alignment tools are placed on the square blocks on the rear of
the camshafts locking them in place
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The exhaust camshaft sprockets and VCC transmission units with timing chains are placed onto their respective
camshafts
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The exhaust camshaft sprockets and VCC transmissions are secured to the camshafts with their respective
single, reverse threaded bolt. Finger tighten only at this point. Install the chain tensioner into the timing chain case
and tension the chain
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Connect an ohmmeter across two of the three pin contacts on the front edge of one of the VCC transmissions.
Twist the inner hub of transmission to the left (counter clock- wise). Make sure the ohmmeter indicates closed
circuit. This verifies that the trans- mission in the default maximum retard position
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Using an open end wrench on the camshaft to hold it in place, torque the VCC trans- mission centre bolt to
specification.
Camshaft Impulse Wheel Position Tools
The camshaft impulse wheels require a special tool set to position them correctly prior to torquing the retaining nuts.
The impulse wheels are identical for each cylinder bank. The alignment hole in each wheel must align with the tools
alignment pin. Therefore the tools are different and must be used specifically for their bank.
The tool rests on the upper edge of the cylinder head and is held in place by the timing case bolts.
VCC Solenoid Replacement
Refer to the Service Procedures Workshop Manual for complete solenoid replacement procedure.
The solenoids are threaded into the oil distribution flanges through a small opening in the upper timing case covers.
VCC Transmission Retard Position Set Up Tools
A special tool (see Service Procedures Workshop Manual for correct tool number) is used to rotate the transmission
to the full retard position when checking the piston position with an ohmmeter.
This tool engages the inner hub of the transmission to provide an easy method of twisting it to the left for the ohmmeter
test.
Diagnostics
The VCC is fully compatible with the diagnostic software providing specific fault codes and test modules. Additionally,
diagnostic requests section provides status of the PWM of the VCC solenoids and camshaft position feedback via the
camshaft position sensors. The Service Functions section of the TestBook/T4 also provides a VCC system test.