• A failing fuel pump affects the flow of gasoline to the vehicle's engine.gas pump image by jedphoto from Fotolia.com
  
  The 2003 Chevy Tahoe is in between the Chevy TrailBlazer and Suburban in the company's lineup of sport utility vehicles. The Tahoe can carry up to eight passengers and has optional four-wheel drive to assist with off-road operation or adverse weather conditions. A failing fuel pump in a Chevy Tahoe can cause the vehicle problems which may initially be attributable to the engine.
  
  

No Start

• A completely failed fuel pump can cause a Chevy Tahoe to not start at all. If you have the windows down or a door open and the hood up while trying to start the engine, listen for a clicking noise. If there is a clicking noise in the engine bay, then the problem is not the starting system. The next step would be to have the fuel system checked out, including the fuel pump. The complete failure of the fuel pump means no fuel will make it to the vehicle's engine, resulting in the engine not starting. This problem is often preceded by hard starting when the engine has trouble starting up after sitting for a time.
  
  

Rough Idle

• If while sitting at lights, in drive-throughs, etc. the Chevy Tahoe idles roughly, a failing fuel pump is a likely cause. Rough idle occurs when the truck's RPMs fluctuate slightly, and the engine sounds like it is struggling to keep running. If the fuel pump is not functioning properly, the engine may be getting only a portion of the fuel it needs to run properly, resulting in the engine struggling to maintain an idle.
  
  

Loss of Power

• If the fuel pump is failing on a Tahoe, it can cause a sudden or even gradual loss of power in the vehicle. Your Tahoe may begin to struggle to reach or maintain freeway speeds or climb steep grades. Sometimes this loss of power can be accompanied by the engine stumbling or completely stalling out under heavy acceleration necessary for getting on the freeway or climbing a hill. The Tahoe's engine is starving for fuel due to the failing fuel pump and is not able to sustain heavy activities without problems.