I have a 2000 Chevy Tahoe that wont start. I have replaced the fuel pump and filter. It wont start especially if it is cold. I spray some ether in the air filter and it will start. How do I fix..help.?

Could be several things, Crank sensor on distributor, bad oil pressure switch, bad computer. If you cycle the key on then off, do you hear the fuel pump run? When you try cranking the engine what is the oil pressure gauge at 350 Vortec engines require 20+ psi oil pressure to trigger the distriuter to fire.