A VCT system having a housing, a rotor, a locking pin, and a spool valve. The spool valve has a spool slidably located in a bore with a plurality of ports. The spool has a plurality of lands that block the ports. When the spool is in the advance position, the plurality of lands allow fluid through the ports from the retard chamber to the advance chamber. When the spool is in the retard position, the plurality of lands allow fluid through the ports from the advance chamber to the retard chamber. When the spool is in the null position, the plurality of lands allow fluid from a source to the advance and retard chambers. When the spool is in the locked position, the plurality of lands allow fluid supplied to one of the advance chamber or the retard chamber to move the locking pin to a locked position.

 
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