Vortec No Start

The vortex engine is perhaps the best engine GM has with the exception of the 3.8 and in my opinion that can’t be beat. However the Vortec has some problems mainly with the fuel. The pressure and volume has to be right on specs. If you have spark and you have to have spark or at least a tach signal for the PCM to power the fuel pump relay and is improbable but not impossible to have a tach signal and no spark. Check the fuel supply. If you have a Vortec engine that will not start cold at times but always starts hot it is usually a fuel problem and it may be a filter but this should also cause problems at highway speeds. Spray carb cleaner into the throttle body and if it starts it is a fuel problem. I have a refillable spray can that I put fuel in but as most DIY will not have this carb cleaner will work just do not use too much 3 or 4 short squirts should do it. It may not start but if it tries to you know you are on the right track. The other problem the Vortec has is the lines in the fuel distribution system crack or the poppet valves stick this usually causes a no start or extended crank with a hot engine it may also set a rich fuel code. You do have to remove the upper manifold to check this Distribution rail, or octopus, it has come down it price some but it is still expensive. You can pull the plugs and check for excessive fuel in a cylinder and this is an indication of a stuck poppet valve.FYI If you have a jerking problem that feels like a transmission or torque converter problem replace the fuel filter 9 times out of 10 it will solve your problem.If your engine not a Vortec, starts fine cold but has an extended crank time hot check the Fuel regulator.