Small Block & Big Block Chevy Specific - Sbc 350 tbi help!




View Full Version : Sbc 350 tbi help!


EnragedHawk
07-14-2011, 09:34 PM
Ok, I'm new here. I've been using the H.A.M.B. because I'm more of a hot rodder, but it turns out my 350 TBI is too "nontraditional" for them to help me out.

So, here's my problem. I have a 1990 Chevy 350 TBI engine that I have put into a 1955 Chevy Panel Truck, and I think I'm having trouble with the computer. I have been searching all over google to figure this out, but have had no luck. Here's what's going on:

The engine cranks and has spark. I can force the engine to fire up by dumping fuel into the throttle body. Currently, my injectors are not firing. I have 12+ on one side of each injector, but I do not get the - pulse from the ECM. I can jump the wires at the ECM and force the injectors to fire, so I know there's nothing wrong with them.

So, from what I can tell, either my ECM is bad, or it's not receiving the signal it needs to fire the injectors. I have thought that it may be the pick-up coil, but I don't know how to test for that.

ANY HELP WOULD BE AWESOME!


87silverbullet
07-15-2011, 03:32 PM
Ok, I'm new here. I've been using the H.A.M.B. because I'm more of a hot rodder, but it turns out my 350 TBI is too "nontraditional" for them to help me out.

So, here's my problem. I have a 1990 Chevy 350 TBI engine that I have put into a 1955 Chevy Panel Truck, and I think I'm having trouble with the computer. I have been searching all over google to figure this out, but have had no luck. Here's what's going on:

The engine cranks and has spark. I can force the engine to fire up by dumping fuel into the throttle body. Currently, my injectors are not firing. I have 12+ on one side of each injector, but I do not get the - pulse from the ECM. I can jump the wires at the ECM and force the injectors to fire, so I know there's nothing wrong with them.

So, from what I can tell, either my ECM is bad, or it's not receiving the signal it needs to fire the injectors. I have thought that it may be the pick-up coil, but I don't know how to test for that.

ANY HELP WOULD BE AWESOME!

Is the pcm grounded? The pcm needs ground to give ground to feed circuits.

Check your ignition module also. They are cheap and easy to change.

LilJayV10
07-20-2011, 07:21 PM
Do you know if the ECM has VATS or not? The pick up coil and the module work together to fire the injectors if I remember right.