95 S-10 complete electrical failure(engine too)

Hello, My 95 S-10, 4x2, 2.2l, 5-speed 135k has a electrical problem. While driving I get a electrical short(or hiccup?) which makes the radio pop(if on), lights dim, engine miss, and if I'm really lucky a complete shutdown of everything. Luckly I am able to restart it again within a few moments and continue on my way. When this happens the SES light comes on briefly followed by the brake light and then go off. No trouble codes from the computer(grrr). I replaced the battery, alternator, the top of the positive terminal(coroded), and those 2 relays under the hood. I have also checked the fuses and all the grounds I could find. From what I have learned the next step is the ignition switch which is not only very expensive but beyond my capabilities. Anyone have this problem or any advice? Thank you.

Get a volt/ohm meter and check for where it is losing voltage.
Start at battery and battery cables and work on to fuse boxes and switches.

Hi, MT I forgot to mention that the problem only happens when the engine is under load. Would I be able to see a voltage drop at idle? Thanks for replying.

Hi, MT I forgot to mention that the problem only happens when the engine is under load. Would I be able to see a voltage drop at idle? Thanks for replying.

Turn all electrical stuff and try it. Then speed up the engine and recheck it.
It should show up.
And do not forget to test battery out good.
Weak cell or bad battery will mess it up to.
Post back how it goes.
Good Luck.