So as I have posted before I have an extremely rough idle at cold start and it makes me cringe every time I start it. I have been looking at a few different methods of removing the buildup and the best is obviously walnut blasting. As this can get very expensive and inconvenient at the stealer I looked up other options. The soak and scrub! What have people tried themselves? Has it worked? If you could start from day 1, would you buy the same equipment? Depending on the price gap I would like to get a blaster, but i don’t want to spend a fortune on the worlds best one either. I have no issues resorting to the spam and scrub but I do not want to put anything that isn’t supposed to be in my engine, well, into my engine. The soak and scrub I saw was brakleen and a brass brush. What if the brush sheds and gets some bristles into the engine? Just want to make sure I will not harm my beauty. Also are there any special tools involved?