Class A 1996 Chevrolet 454 engine starting problem

Check for battery voltage at coil and module with key on. If you do, suspect pick-up coil. Gently tug and move wires from pick-up coil to module and feel for broken wire. Also, if you have a multimeter, disconnect the pick-up coil from the module and ohm the pick-up coil. It should show some small value. Also, you can connect the multimeter to the pick-up coil connector and with the meter on AC, crank the engine and look for a reading. Probably less than a volt. This should either confirm or eliminate the pick-up coil as a cause of no spark.

What injector pump? 7.4 TBIs do not have one.

The injector pump is heard when key is turned on, and before engine is cranked. The distributor cap, rotor, coil, and module in the distributor have been replaced.

Trail-Mate wrote:
On the TBI GM Motors the module in the distributor will cause this issue. Random starts then No start at all. Easy to change and not expensive. If this does not solve it then connecting a fuel pressure gauge to the port in the rear of the TBI to test Pressure. Peak Pump pressure on the TBI motors is about 15-16 psi, and regulated by a regulator in the back of the TBI, There are way to change the regulator pressure but would have to look up how to do it, but the regulator is not your problem anyway.

I'm sorry, I disagree with you. There is not any sensor anywhere on the chassis that will prevent the pump from pumping fuel when the ignition is first turned on. This is a pre-start condition that is commanded from the ECM, to provide fuel in preparation for the engine to start. This occurs regardless of if the engine turns over or not. Same with the injectors. The injectors are pulsed initially, regardless of if the engine turns over. Basically, they put some fuel (rich mixture) into the intake so when the engine cranks, it will start.

See, if we hear the injectors fire when the key is turned on, then we know there is power to the ECM. Right now, we have no proof the ECM even has power. As a matter of fact, there is some indication that the ECM is not getting power, because of the lack of fuel when the key is first turned on, as well as the lack of spark, once the engine is cranking. So, that is the reason we want to listen for the injector pulse when the key is first turned on (before cranking). If we do not hear that injector pulse, then the ECM has lost power, and all these other symptoms are secondary.

On the TBI GM Motors the module in the distributor will cause this issue. Random starts then No start at all. Easy to change and not expensive. If this does not solve it then connecting a fuel pressure gauge to the port in the rear of the TBI to test Pressure. Peak Pump pressure on the TBI motors is about 15-16 psi, and regulated by a regulator in the back of the TBI, There are way to change the regulator pressure but would have to look up how to do it, but the regulator is not your problem anyway.

To answer the OP question: No, fuel delivery is not required for spark to occur. In fact, I don't know of any engine management system that does.

So, if you don't have spark, look to the module or reluctor pick-up coil. Lack of fuel is a different issue.

Agreed. His original post stated, "After cranking with no spark, there is no smell of gasoline with air filter removed. Thought problem could be fuel pump or fuel filter." Having a look into the Throttle Body will answer the question of whether the engine is getting fuel.

Dachristianman wrote:
I agree with Daveinet. You can look into your TBI and see if it's squirting fuel into the engine. That's an easy place to start.

I want to be clear though, we are asking for more specific information - do you hear the injectors click when the ignition is first turned on. Fuel flow is a separate question that requires a separate answer.

Fuel will only squirt if the fuel pump has applied sufficient pressure to the line.
If the fuel pump relay has not run for the two seconds, there will be limited pressure.
In "run" position the fuel pump will not run with out oil pressure.

I agree with Daveinet. You can look into your TBI and see if it's squirting fuel into the engine. That's an easy place to start.