1988 Chevy c3500, injector spray dies out when throttle is pressed

Forgot to mention, it is a 2wd drw with a sm465

Whats your map voltage at idle, i dnt think this has mass air flow sensor does it?

I will check it in the am, but it is new, I thought that was my problem at first so I replaced it with a new one, it still acted up so I swapped it with one from my other truck that runs perfect an still no help

No mass air flow sensor, it seems to me that something is causing the injectors to shut down when the throttle is pressed, if they were plugged, wouldn't it idle funny too, and not spray correctly? I've checked them under the timing light and there is no difference between them and the ones on my other truck at idle.

Sounds more like the computer cant determine proper fuel delivery or you have some kind of fuel volume loss, such as reatrictions or bad power/ground maybe.. when you tested amperage what reading u come up with

It was running around 5 amps. I ordered a new ecm, that was going to be my next guess. Lol. I don't know how to test the in I have though

When I tested the pressure it was idling at about 11 psi or so, but it will idle fine for a bit then get choppy, sometimes die. I have to feather the throttle to keep it going for the most part, it will try to die when I hit it but as soon as I let off it jumps back up in idle. I will get random backfires depending on how fast I pump the accelerator to keep it running, and it doesn't seem to run much higher than 1200-1500 rpms. The symptoms are that of a bad fuel pump, but everything on that end checks out and is brand new.

Thats good amperage, what id do is make sure your map sensor is getting a proper power/ground.. it doesnt surge or anything does it

It does, it will run fine for a minute maybe, surge for a few seconds, sometimes enough to stall, and sometimes it picks back up. If I understand plug it, it will idle higher, but still do the same thing.

Un plug* (autocorrect)

Surging is indication of running lean

I know, lol. It leans out severely when I hit the throttle, I just don't know what would cause the injectors to basically close up when I do, besides the ecm, at this point. I guess I'll have to wait and see, if it's not that then I don't know what else it could be, the probability of both injectors doing the same exact thing at he same time seems a little odd, as far as having them both go bad at the same time the same exact way

Well if u had a way to scope the injector you could see of your losing injector pulse... id unhook your battery and let it set long enough to wipe all the learned memory out of the computer and see if it still does it

I've tried that, I've had the ecm completely out, when it's cold and I start it, it idles perfect, no problem, when the choke shuts off it acts up, but I can't hit the gas or it bogs down.

Hmmmm have you tried unplugging the idle air control motor then starting it

Yes, it runs worse, it won't idle with I unplugged, it revs up and surges and dies.

Update, I replaced the computer and Injectors,still not any better, it idles perfect now, but as soon as I hit the gas it wants to lean out and die. New fuel pump, sending unit,filter, plugs, cap, rotor, distributor, Icm, tps, iac, coil pack, computer, injectors, egr delete for quite some time, tbi rebuild with new regulator spring. There is nothing left to replace, no codes.. still looking for suggestions.

Still looking for help. I've been tracing wires and haven't found any bad ones, grounds are all good. Any advice?

Problem solved, ended up being a bad injector wire, it was cracked and grounding out on the motor. Thanks for the help