Apu rough idle/blowing soot

Ok, so I just got my Thermoking APU out of the shop, the belt was squealing and I had what I thought was an injection pump issue as well as an exhaust leak, after tightening the belt though it ran just fine with the bottom cover and top cover off with the intake filter out. Now that I have it back at my yard I turned it on so I could start cooling my fridge off to get ready to leave out tomorrow and now it won't run without bogging down and blowing black soot. To be clear it starts up just fine, and then bogs down when the compressor actually kicks on. I can check tomorrow and see if it runs without the compressor on but I doubt that's the actual issue as it ran fine without the casing on and the AC compressor actually coming on. Also no other services were done to the APU either. No fuel lines removed or oil changes in the past 20 days, and it was running fine other than the squeal and the exhaust leak Any ideas would be helpful.

 

It will continue to blow air after it sputters out and then throw the alt code. The fuel pump was replaced like 3 months ago by myself without running it dry, as I replaced the inside filter and fuel pump at the same time. I just bought a new air filter yesterday and installed it, so that isn't the issue. I will attempt to run it without the filter again, and then check the alternator. Mind you though with the ALT code being thrown it doesn't die and throw the code at the same time it dies and then like 4 minutes later it will throw the alt code and shut the blower off. It won't even try to restart.

 

Update, wont run even with the filter out, solenoid appears and sounds like it's working properly.

 

Yeah compressor isn't seized, and it's 100% getting fuel, so pump is working properly