just a simple question really, if I added an in tank injector cleaner would it also help clean the combustion chamber etc,and would it change the octane rating.

 

I am sure that the manufacturer would claim cleaning of everything. The small amount of kerosene that you will be adding to a tank of gasoline will not make any difference in octane.

My personal opinion is that the major fuel distributors have added cleaning properties to their fuel to meet or exceed the auto manufacturers' specifications. Most of the injector cleaning requirement and claims have originated in the marketing, rather than engineering, departments of the various suppliers.

 

Along these same lines, is there anything that will quiet LOUD injectors? I've got a couple that almost sound like loose lifters. Is replacement the only option? Is there any problem driving it this way until they die? Car still runs perfectly smooth.