Lexus SC 430 2004 Manual page 260

NOTICE
Do not pull-or push-start the vehicle. It may damage
the vehicle or cause a collision when the engine starts.
Also the three-way catalytic converter may overheat
and become a fire hazard.
If the engine turns over at its normal speed but will not
start -
1. The engine may be flooded because of repeated cranking.
See "(b) Starting a flooded engine" for further instructions.
2. If the engine still will not start, it needs adjustment or repair.
Call a Lexus dealer, Roadside Assistance or Customer
Service Assistance. (See "Foreword".)
IN CASE OF AN EMERGENCY
(b) Starting a flooded engine
If the engine will not start, your engine may be flooded
because of repeated cranking.
If this happens, turn the ignition switch to "START" with the
accelerator pedal fully depressed. Continue this operation for
30 seconds and then stop cranking. Then try starting the
engine with your foot off the accelerator pedal.
If the engine does not start after 30 seconds of cranking,
release the ignition switch, wait a few minutes and try again.
If the engine still will not start, it needs adjustment or repair.
Call a Lexus dealer, Roadside Assistance or Customer
Service Assistance. (See "Foreword".)
NOTICE
Do not crank for more than 30 seconds at a time. This
may overheat the starter and wiring systems.
(c) Jump starting
To avoid serious personal injury and damage to your
vehicle which might result from battery explosion, acid
burns, electrical burns, or damaged electronic
components, these instructions must be followed
precisely.
If you are unsure about how to follow this procedure, we
strongly recommend that you seek help from your Lexus
dealer, Roadside Assistance or Customer Service Assistance.
(See "Foreword".)
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