Anyone near by good with diagnoses that can lend a hand?

[TylerT/AZ28]

i have a 93 yukon, ive diagnosed everything i can to a degree, im not electrical genius im trying to diagnose everything the best i can. lately ive been throwing code 43 which is knock sensor or spark control. For the life of me i cant figure it out, the truck runs great at high rpms from a stand still but as its picking up speed it stumbles and wants to stall and drop rpms. its only under load though. ive tested everything i can think of and unless im testing things incorrectly everything seems to check out fine.

i cant afford to keep messing with this thing and having it unuseable so can someone lend me a hand one day, or help me diagnose it on here??
i used to have a laptop usable to datalog the truck but the laptop no longer recognizes being hooked up to the laptop.

[NullHead]

So what do you know so far, what have you replaced or figured out yet? Sounds like a vacuum leak or miss fire type thing. What have you done to it recently that might be suspect? Check your timing and distributor for play because the bushings are known for going bad on the distributor and causing all kinds of strange things to happen

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[TylerT/AZ28]

checked for vacuum leaks with both carb cleaner and propane and had nothing, all the spart plugs and wires check out. im throwing code 43 which is for knock sensor or esc. wierd thing is from my findings unless i did something wrong my knock sensor is giving signal to the ecm unless the ecm is toast if it is i havent had any luck finding a new one.

before the issue i had an issue with my positive battery cable dying on me, i fixed that then on the way to school a month ago i nailed it to get past a yellow and it started stumbling when i let off, i limped it home and have been testing everything i can. then decided to fix a few leaks pulled the motor resealed it and put it back in. grounds are all hooked up, tps, iac, 02's are all getting correct signal and it doesnt seem to happen in park or at idle but after about a minute or 3 when the engine a tad warmed up it starts dropping rpm looking to stall and stumbles when you try to take off.

if your in the area and would like to look id appreciate any help i can get.

as far as whats replaced, every sensor, fuel pressure checked, harness was replaced when i first got it as the stock was one hacked together big time, ground straps redone plugs wires and distributor are about 5k old if that. rear end replaced with different gears and locker, motor trans and tcase resealed, has a chip headers, cam, roller tip rockers, intake, head work, new timing chain, coil, tbi redone, etc.

[NullHead]

Have you checked your timing? This is a carb'd engine or TBI?

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[TylerT/AZ28]

Timing set at 0*, TBI

[NullHead]

And its still flashing a code 12(32? Can't remember) for the ECM being alive? So as long as you're sure it isn't misfiring, have you tested your TPS or EGR? I'm not super concerned about the code but its a good indication that something is awry. Check your ECT, TPS and that your o2 isn't melted to the header. Sounds like after the truck gets out of cold start it looks at its sensor inputs and acts according.

Wish my OBD1 scanner worked ...

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[TylerT/AZ28]

ive tried both cold and after running there is no egr its been tuned out, ect, tps, and o2 are fine with both conditions cold and warm. still flashing code 12 for ecm and then 43.