88 Chevy Silverado idling problem

I have a 88 Chevy Silverado pickup 2 wheel drive with a 350 ci engine TBI and automatic overdrive transmission. I have been having problems with it's inability to keep idling.
I have recently changed the spark plugs (gap checked), new spark plug wires, distributor cap and rotor, and new ignition coil. I also have had it into a couple of garages to t'shoot the problem. From the latest t'shooting, the technician indicated after replacing numerous sensors and electronic components that the problems must be related to the main computer or a wiring problem. The technician also indicated that there does not seem to be a pulse signal to the injectors during idling and it only is receiving the 5V operating voltage.
If I keep the engine revved up, it will not stall.
I have since tried replacing the main computer, but this does not remedy the problem.
I have also changed out the transmission as there was a torque converter lock up/stall speed concern.
I have not yet changed the wiring harness.
Much appreciated if anyone can provide some insight.
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it's
wires,
a
be
the
Most likely you need to replace the pick up magnets/coil in the distributor. They are pointed, requires removal and disassembly to replace. Recently we have done about 10 vehicles with this same problem.
Just incase your tech doesn't know, a weak signal from a pick up coil/magnates will cause weak injector pulse (pulse voltage). When the magnets/coils go completely out, you lose all pulse. Charles
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Good pick Charles:
I was going to say that, notice I've been recommending that a lot.
then winter before last, when I was still in the shop. We did more pick ups in that year, than I've done in my whole career as a technician. I think all the recycled copper wire is coming back to haunt us finally?
Refinish King

TBI
into
the
to
the
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ups
all
I don't know what it is, as of late we have had a rash of 87 and up GM HEI's with that problem. It could be the vendor GM used for those, I'm not sure. Most of the one's we have replaced are on vehicles with over 200K. A few on vehicles with over 100K. Mostly C/K Pick Up's, and G-Vans. A few car distributors as well. Charles
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Refinish King wrote in alt.autos.gm
I

What does recycled copper have to do with any problem? It gets melted down and purified just like copper ore does.
--
Dick #1349
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Really?
You're a metallurgist?
Have you ever seen the size of the wire of the electromagnetic coil in question?
Just wondering?
As I don't know anything about melting and purifying metals?
Refinish King
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Refinish King wrote in alt.autos.gm

The one in question? No. But I have seen plenty of coil wires, and they are all very small. Now, back to my question, why do you think that there is a problem with recycled copper?
--
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