Change start procedure:

1) Turn key to #2 position.

2) Wait exactly 30 seconds.

3) Start engine and immediately increase speed to 1500 rpm.

4) Hold 1500 rpm for 30 seconds.

5) Release throttle and allow to idle normally.



The ticking sound that comes and goes is the lifters. Just about every 603 has this unfortunate characteristic. It's been claimed that Mobil-1 will cure the problem after 10K miles if you'd like to give it a shot.