Patent Number: 6,612,288

Title: Diagnostic method for variable compression ratio engine

Abstract: A diagnostic method for a motor vehicle having an internal combustion engine operable in a plurality of compression ratio operating states includes the steps of determining a change in spark adjustment required to avoid knock as the engine is operated in selected ones of the compression ratio operating states, and evaluating operation of the internal combustion engine based at least in part on the change in spark adjustment.

Inventors: Cullen; Michael John (Northville, MI)

Assignee: Ford Global Technologies, LLC

International Classification: F02D 41/22 (20060101); F02D 37/00 (20060101); F02D 37/02 (20060101); F02P 5/152 (20060101); F02D 15/00 (20060101); F02D 15/02 (20060101); F02P 005/00 ()

Expiration Date: 09/02/2020