When I pulled my fail rail this morning, I looked through the port holes in the engine where the injectors penetrate and noticed that they were really grimy inside. Is there a safe way of cleaning that out? Is there any type of cleaner that would be safe to spray in there?

 

There are probably lots of choices, such as carb cleaner, starting fluid, brake cleaner, electrical contact cleaner, MAF cleaner, naptha, or anything else that will leave zero residue when it evaporates. I would try to avoid using a spray if possible, by beginning with a shop vacuum to remove as much gunk and grit as you can, then wiping with Q-tips/cotton buds and paper towels twisted into "cleaning rods" moistened with whatever cleaner or solvent you have on hand, to minimize the amount of gunk that is washed down onto the intake valves and ultimately into the combustion chambers.

I'll be curious to hear what others recommend.

Cheers,

Don