A pump keeps the pressure constant at 24,000 PSI as it sits waiting for delivery to the combustion chamber via fuel injectors, one at each cylinder. Fuel is forced through the injectors sequentially as the onboard computer directs them to fire (open).
Common rail injection
From Christine & Scott Gable, former About.com Guide
This is the left bank fuel rail of the CRD (common rail diesel direct injection) system.
photo © Adrian Gable©2009 About.com, a part of The New York Times Company.
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