Had just got done finally sorting out the brake issues with my s13, went out for a test drive and after I stopped at a stop sign, the car stalled. Started back up and pulled into a parking lot and noticed a cloud of white smoke come from the bay. Opened the oil cap and smoke came out of the valve cover. No smoke from the exhaust. Got going again and stalled at another stop sign, this time would not start again. Pushed it into a parking lot and waited, after a few minutes it started up again and I limped home. Its making a rattling noise which I'm going to guess is rod knock or timing chain rattle, it gets worse with rpms. I've never done any racing or drifting with this car, it was supposed to be a daily. I'm guessing the motor is toast?