Lotus 2004 ELISE Service Notes page 266

Lotus Service Notes
When the ignition is first switched on, the engine management ECU energises the fuel pump for a period
of about 3 seconds to prime the system before switching off. If a signal from the crankshaft sensor indicates
that the engine is being cranked or is running, the fuel pump feed will be maintained. The pump is switched off
immediately when the ignition is switched off, or about 3 seconds after a stall. Note that if coolant temperature
at the time of ignition switch off is over 88°C, the ECU remains powered for a period of 20 minutes to allow for
heat soak management (see sub-section KH.5). Re-energising the ignition during this period will not run the
fuel pump until the ECU receives a crank signal.
A safety inertia switch is incorporated into the fuel pump electrical circuit, and operates in a severe impact
(indicative of a vehicle collision) to switch off the fuel pump feed and minimise the fire risk. The switch is located
in the engine bay on the inner face of the left hand chassis siderail, and is reset once tripped, by pressing the
rubber button on the top of the switch.
An evaporative emissions 'charcoal' canister is mounted at the right hand front of the engine bay and is
connected to the air space inside the fuel tank via the FLVV and fuel pump top plate as previously described.
The purge port of the canister is routed through a solenoid valve mounted on the inlet manifold, to a port on
the intake plenum. The evaporative emissions control system prevents untreated fuel vapour from the tank
reaching the atmosphere, by absorbing the tank vapour in a bed of activated charcoal in the canister. When
the engine is running, the engine management ECU opens the Vapour Management Valve (VMV) and allows
intake manifold depression to draw fresh air through the canister, purging absorbed fuel from the charcoal, and
consuming the resultant vapour in the normal combustion process. In this way, the charcoal bed is 'cleaned'
ready to absorb more tank vapour.
LK.2 - FUEL FILLING
Fuel Requirement
USE UNLEADED PREMIUM GRADE GASOLINE.
Use only unleaded gasoline meeting ASTM specifications. Use of fuels not meeting ASTM specifications
could cause poor performance and increase emissions.
For optimum vehicle performance and fuel economy, the use of super or premium unleaded gasoline, with
a minimum octane rating of 91 (RON+MON)/2 is recommended. Where super or premium fuel is not available,
the Elise will operate satisfactorily on unleaded gasoline having a minimum rating of 87 (RON+MON)/2, but
vehicle performance and economy will be reduced. Using fuel with a lower octane rating may cause knocking
(pinking) which, if severe, can cause serious engine damage. Light knocking may occasionally be heard for
short periods when accelerating or driving up hills, and this should cause no concern, although using a lower
gear would be advised. If, however, persistent heavy knocking is heard when using the specified fuel, the cause
should be ascertained without delay.
The use of good quality fuels containing proper detergent additives is advised for good performance and
emission control.
Do NOT use leaded fuel: damage caused by the use of leaded or other improper fuel is not covered by
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Fuel pump inertia switch
Section LK
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