[bimmerboi318]

It's hard to diagnose that kind of problem without actually seeing the car, but I would get a stethascope and start poking around. If it's coming from the front timing case, I'd say the timing chain and tensioner(s) need replacement. If it's higher and on the valve cover or farther back on the engine, then lifters, rockers, followers, etc are suspect. I'm not sure how involved it would be to replace those, I've only done valvetrain work on cam-in-block motors, which are fairly easy. Our DOHC engines may be different...You may need someone (or a shop) listen to it for you.