Vortec 2.9L I-4 Engine

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The Vortec 2.9L I-4 engine in Colorado is smartly engineered to be powerful, efficient and durable. It generates 185 horsepower at 5600 rpm and 190 lb.-ft. of torque at 2800 rpm and includes the following features:

• A broad torque curve through the majority of the speed range helps this engine deliver 90 percent of peak torque from 2400 to 5700 rpm, providing ample torque at low rpm and high rpm. The result: a truck that responds with the torque you need, when you need it.
• Electronic Throttle Control (ETC) relays accelerator pedal information to the Powertrain Control Module (PCM). The PCM then positions the throttle air valve in the best position to help achieve optimum vehicle drivability.
• Pistons and rods are lightweight, which help the engine run comfortably at high rpm and produce more power from smaller displacements.
• Variable Valve Timing (VVT) offers a number of advantages over conventional valve timing in the areas of power, efficiency and emissions and helps produce near-peak levels of torque over an extended range.
• Dual balance shafts offset the secondary forces generated by piston movement and help provide smooth, quiet operation throughout the entire rpm range.
• Premium aircraft-grade A356 aluminum and an advanced heat treatment process give the engine block and cylinder heads light weight with exceptional strength.
• Nodular iron crankshafts were optimized using the most advanced math-based computer tools available to GM to help provide quiet operation, long-term reliability and remarkable durability.
• Iridium-tip spark plugs enable the vehicle to travel up to 100,000 miles before the plugs need to be replaced. The recommended engine coolant change interval is up to 5 years or 150,000 miles (whichever comes first). And the accessory drive belt is designed to operate up to 150,000 miles before requiring replacement. Maintenance needs vary with different uses and driving conditions. See the Owner's Manual for more information.