2010 GMC Sierra 1500 Crew Cab Owner's Manual - Page 165

2. If the engine does not start after 5‐10 seconds, especially in very cold weather (below 0°F or −18°C), it could be flooded with too much gasoline. Try pushing the accelerator pedal all the way to the floor and holding it there as you hold the key in START for up to 15 seconds. Wait at least 15 seconds between each try, to allow the cranking motor to cool down. When the engine starts, let go of the key and accelerator. If the vehicle starts briefly but then stops again, do the same thing. This clears the extra gasoline from the engine. Do not race the engine immediately after starting it. Operate the engine and transmission gently until the oil warms up and lubricates all moving parts. Notice: The engine is designed to work with the electronics in the vehicle. If you add electrical parts or accessories, you could change the way the engine operates. Before adding electrical equipment, check with your dealer. If you do not, the engine might not perform properly. Any resulting damage would not be covered by the vehicle warranty. Fast Idle System Fast Idle System with Switch If the vehicle has this feature it is available only with cruise control. The manual fast idle switch is operated using the cruise control buttons located on the left hand side of the steering wheel. This system can be used to increase engine idle speed whenever the following conditions are met: ... The park brake is set. The brake pedal is not pressed. The vehicle must not be moving and the accelerator must not be pressed. 3-27