I bought a 300zx z32 1989 N/A 2+0 Manual 4 months ago and it had a misfire. The misfire was the injectors/ injector plugs. I ended up doing a plenum pull on it and replacing injectors, injector plugs, coil packs, spark plugs, rocker cover gaskets. now that I've replaced everything it had a couple vacuum leaks which cause it to idle surge, I replaced a bunch of hoses and now it just doesn't want to idle by itself. I've set the throttle position sensor to what its meant to be. I've also notice soot from the exhaust and when it's running it still feels lumpy likes it's still got a misfire. I believe its putting too much fuel into the cylinders because I pulled out the new spark plugs, and they were sooty. I'm just a bit stuck on where to go next. i want to get this gem on the road asap but I'm pulling my hair out just thinking about it atm.