The general meaning of the engine C1451 Code is automobile meaning and this meaning is C for Chassis Code Problem is controller area network wiring bus and modules. 1 for MFG – Manufacturer Specific. 4 for Transmission. 5 for TP Sensor Learn Not Complete and 1 for TFP Valve Position Switch-Drive Without Drive Ratio. The C1451 engine code is a kind of chassis problem and no component is necessary to change for solving the car engine problem. The car engine system services particularly advanced hydraulic lifters for the engine C1451 code intake and finish valves. The lifters can be misshapen by disengaging an inner locking pin.