Truck won't start

[spdy70]

I have 1988 chevyt pickup and the injectors are not spraying fuel. I fist thought it was fuel pump and then I replace the throttle body due a dumb thing and still won't start. In cranking it over can't see the injectors spraying fuel and need a direction to go Thank you for any assistance.

[2000CAYukon]

On the TBI trucks, the pickup coil signal (which is AC) is converted to DC by the ignition module and then sent to the ECM. The ECM uses this DC signal to fire the injectors.

Some parts stores can test the ignition module and that is where I would start looking.

//2000CAYukon

[maxwedge]

Welcome to AF. Check the fuses for the injectors, do you have spark? Check for pulse at the injector harnesses with a " noid" lite, this is all basic diagnostics.

[spdy70]

Thank You I will look at the Ignition Control module and go from their. The other post said something about a noid light at the injector wiring harness. Does the ignition switch have to be on test? I suppose that you unplug injector and test at this site.

[twistedtech]

On a tbi rig take the test light an key on you will find power to 1 side of inj. Other is ground, pcm grounds other to make it fire. You could use both sides to power test light. 1 ground 1 power.No it don't matter either 1. Roll it over, if it flases you have injector pulse.If not, look at module.

[spdy70]

I want to thank the ones who have responded, it was the module. I finally look at that and it had a yellow dot on it. So I replaced it with aq new one. The truck starts and idles pretty good. I due have a little miss, but I think that it may be related to a plug wire boot being split. So I will put new wires on it tomorrow. Again thanks.