2003 tahoe problems

Could be sparkplugs, ignition wires, or even clogged injectors.

The key issue is a good clue. Your key has a small chip in it and has contacts on the sides which can wear. Compare his key to yours. Also, bad ignition switch is possible. Check to see if yours is part of the ignition switch recall.

When you turn the ignition key to the on position can you hear the fuel pump running?
The fuel pumps are notorious for failing. The fuel pump is located in the gas tank and you'll have to drop the tank to replace it.

oh man, have you tried turn the steering wheel to release tension on the ignition lock at the same time you open the ign??????? other than that either the plunggers inside are broken or your key is bent or bent. good luck

it sounds like the problem but the question is why wont the pcm start the car. with the key turned to on the service engine light sould be on. if not the pcm has no power.

Turn your key to the on position(do not start), then push the throttle pedal to the floor three times, turn of the ignition, wait a second or twothen start the engine, this should reset it. Works on the 2000 Tahoe LT 4WD

i have the same problem with my corolla 2002 I turn off the keys and put it out and the engine still running, I uplug the EFI fuse and the engine stop, I guess I need to replace the ignition.. or i'm wrong???

If he had it started two times without the key , i would think it was the starter either . Do you an the guy who replace the ignition switch know how the starting system on your tahoe works ? Do you know what a neutral safety switch is ? Try moving the gear shifter to neutral an see if it starts then . That is if your tahoe has a automatic transmission . When you turn the key to the start position this sends a voltage signal to the PCM - engine computer which inturn will energize the starter relay , closing the contacts sending B+ voltage to the starter solenoid , spinning the engine over . Using a factory scan tool you would be able to see if that start signal from the ignition switch is making it to the PCM . Also would be able to energize the starter relay with the scan tool to see if the computer can energize the starter relay . You could also do testing with a DVOM - digital volt ohm meter . Find the PCM an connector 2 pin #59 , this is the circuit for start from ignition switch . Have someone turn the key to start , is there B+ voltage ? Find the starter relay in the under hood fuse box, pull it out an look on the bottom . You will see four sets of numbers 30 , 87 , 86 , 85 . If you take a piece of wire an jump 30 an 87 in the fuse box the starter will crank the engine , or spin the engine . If you do that and it won't start , cables , connections or the starter is the problem .

need to check the engine timing and to make sure you have the right octune of fuel in your car.

you have a fault somewhere my best bet is to take it in for a check up