While driving home the van just shut off and would not start, had it towed home?

Had timing belt replaced 2 months before the problem, driving home van just shut off, wouldn't start had it towed home. The next day cranks over, no start, finally got it to start, running really rough and valves rattle, when given gas loss of power. I put the scanner on and get no codes, replaced crank position sensor, cam position sensor idle control valve, coil, wires, plugs, fuel pump and filter, it's getting spark, fuel. After all of that, I took it back home because the garage here in my town likes to rip people off I found out thank you very much. I'm at wits end, and known has an answer. I've been on the web and called all over, and all that work done, hasn't changed a thing, still won't start most of the time when it does, low power, valves rattle like crazy, it has been well cared for, and I need it and can't afford to buy another vehicle, I am pretty mechanically inclined, I don't know what else to do and desperately need help, I was giving up and then I ended up here, I would appreciate your advice, as this is my last ditched effort, I've been dealing with this for 3 month, it doesn't smoke, no backfires, I don't get it, thank you so much for what you people do, I'm not a mechanic but kind of the same thing is happening to my 2012 chevy malibu 2.4liter. I also had my timing belt replaced in Nov. When mine dies and won't start back I take the battery cables off hold them together for 60 sec. Then leave them off for 30 min. Or pull out the ECM Fuse and put it back in. My car also doesn't throw any codes and it sounds like a rod is going to come through the motor or something when it's about to shut off. I'm going to try to replace the crank shift position sensor hopefully that's what it is. Good luck, I hope we both figure it out! Thank you for your time.