JK1500

Hello all. This if my first Chevy, I have owned for about a year. Its a 3rd vehicle/tool box to use around our property, hauling, hardware store etc. runner. Anyways since I bought it, I dont drive it in the rain because I had no wipers. I fixed that recently along with a slew of other things because I want it to start every time and not leave me stranded. Anyways I drove it in the a nasty Florida storm yesterday, first time and after about 45 minutes, she was stumbling bad and had no power, I just eased the gas and then it would wake up and go for a bit and then miss fire like crazy. I babied it home, check engine light came on and went off but just pulled the codes. I thought to myself it has to be a moisture issue? I feel like I have read this somewhere before? I have rebuilt the distributor, changed the pickup, changed that computer board in there, cap and rotor, plugs wires, coil, since I have owned it, alot of these parts are only a few months old if that. New O2 sensor, egr, parts list goes on and on.

1994 5.7 350

These are codes: 38, 42, 44.
38: TCC brake switch circuit error
42:Ignition bypass circuit error
44: Oxygen sensor error (lean condition indicated)

Hopefully those are the right codes per google.

Anyways I go out there, she starts and runs fine but it isnt rainy, its a nice day out. Drove down the street etc. no issues whats so ever. My wife went to get plants this afternoon, I she was with me and I was pulling a trailer when it was acting up. I couldnt convince her to take it, she drove her SUV.

Any Ideas?

Little Bear

Sounds like bad plug wires, even though new. My suggestion is after dark open the hood and start it up and look for sparks/arcing from the plug wires to metal. If you don't see anything mist the wires with water and see if that shows anything.