I got a vr4, i am trying to restore. I have know knowledge on those type of vehicles.i got the car with a rod knock, which I replace the engine and I got a mistfire. The car sound like a subaru lol, the plugs at the front looks ok but the back are black. i am getting spark and fuel in all cylinders idk wat else to do I think I got low compression that's the only thing I can think of. my next step is to run a compression test, also the engine I removed didn't had a misfire from my knowledge.