1994 Mazda b4000 4.0 rough idle and codes

[callmedak]

New to the site but I’m clueless and it’s worth a shot but I’ve recently gotten a 1994 Mazda b4000 it’s got the 4.0 and automatic trans. When I got it it ran but rough and shook the entire truck at first it had limited power but it had plug wires swapped around and fixing that sort of cleaned up the limited power but still has rough idle and dies sometimes even dies when driving. the previous owner threw every part they could think of at it and still didn’t fix it. I know every sensor has been replaced and still pretty much new along with plugs/wires/ignition coil/starter/alternator/iacv. I’ve checked the codes and it threw a list which I attached and it just makes more confusion. I’m not sure what to do but suggestions would be great.

 

[Shran]

I would check all your grounds, with codes like those. Should be a couple on the radiator core support, one or two under the dash... negative battery cable... etc. A lot of sensors share a common ground and I am betting there's a wire broken or disconnected.

 

[callmedak]

I would check all your grounds, with codes like those. Should be a couple on the radiator core support, one or two under the dash... negative battery cable... etc. A lot of sensors share a common ground and I am betting there's a wire broken or disconnected.

After looking over the truck grounds I found the battery ground was ran to one of the starter bolts with a ring terminal and it was loose as well as I found the battery power wire was half way melted I’m not the best with electrical could the loose ground really make that much go wrong?
Update- even after cleaning surfaces and redoing the ground it made no difference

 

[Shran]

Yeah, a missing or loose or corroded ground can cause all sorts of problems. I would pick a sensor... say the TPS maybe would be a good one. Key on, engine off you should have one wire grounded, one wire with about +5v, and one wire that will have positive voltage that varies with the throttle position.

I believe the Gray/Red wire will be your ground... check continuity to the battery negative post or the frame or engine block. Should have continuity there. If you have no continuity, there is a good chance that none of the other sensors that share that ground have a ground either thus the fault... trace it back to where it's bad.

Gray/white is your signal return, variable voltage
Brown/white is your +5v power

See the little dot on the bottom middle right above the word Engine where all the wires come together? That whole spaghetti mess is a shared ground for everything those wires go to.