Misfire - Lotus Evora Service Notes

Lotus Service Notes

Misfire

P0300 Random/Multiple Cylinder Misfire Detected
P0301 Cylinder 1 Misfire Detected
P0302 Cylinder 2 Misfire Detected
P0303 Cylinder 3 Misfire Detected
P0304 Cylinder 4 Misfire Detected
P0305 Cylinder 5 Misfire Detected
P0306 Cylinder 6 Misfire Detected
Description
A misfiring cylinder can be detected by analysing crank speed variation. As a result of a combustion event there
will be a net acceleration of the crankshaft. Subsequent to a misfire event the engine will decelerate over the
period following the missed cylinder event.
Speed changes can be characterised by observing changes in the time period for a fixed angle of rotation after
firing events. A significant change in this period, assessed by comparison to previous periods, may be attributed
to misfire on a known cylinder.
Component connections
Connector Description
1 Supply Voltage
2 Ignition Coil Feedback
3 Coil Output (Logic)
4 Ground
Malfunction Criteria
The operation of all the misfire codes is the same, the last digit relates to the misfire involved i.e. a code P0303
indicates there is a problem with cylinder number 3.
P0300 indicates the misfire is random and not linked to one particular cylinder.
Monitor:
• Continuous
Enable Criteria:
• Battery voltage between 10 – 16 V
• Coolant temperature between -10 – 120°C (14 – 248°F)
• Engine speed between 480 – 8010rpm
• Engine speed transient > 15rpm
• Altitude < 8000 ft (2438 m) / Baro > 756mbar
• Fuel level > 5 litres (1.3 US gallons)
• Engine load greater than 14 – 25% depending on engine speed
Disable Criteria:
• DFCO enabled (Deceleration Fuel Cut Off)
• Rough road
• MAF faults
Malfunction Criteria:
• Individual cylinder misfire in excess of 10% of total engine misfire
• P300 set when more than one cylinder misfiring or when CAM error MIL requested
Limp home (depends on severity and number of cylinders affected):
• Throttle limited and engine continues to run on all cylinders
• Fuel system set to open loop control
• Affected bank shut down and engine speed limited to 4000 rpm
Page 34
ECU Pin
Coil 1 Coil 2 Coil 3
D2 D2 D2
F4 F3 F2
2009/02
Section EMR
Coil 4 Coil 5 Coil 6
D2 D2 D2
F1 E4 E3
ECU Connector
32 Way (Left)
32 Way (Left)