Well, I was doing some thinking, and looked up the procedure to do a hot soak on the 318. I follow how it's done, but there are a few things I couldn't find an answer for.
1. My dad says that when he ran ARCA and SCCA back in the 60s and 70s, people would use water for a hot soak procedure. Since water has a higher heat capacity than alcohol (which is in the usual cleaner), it would seem this would work better. Does it?
2. Some gas companies claim to put lots of cleaners in their fuels as is. Does using this type of fuel negate the need for the soak?
3. Also, how can I tell if the cleanout is even needed? The Bimmer idles well except when it's really cold, and even then it settles down in about ten seconds.
4. What are the odds of doing any kind of damage to the motor with this? Is it just keeping an eye on the gauges to make sure it doesn't overheat, or something more serious?