# Is there a substance that will eat through and completely dissolve carbon but not damage engine cylinder, piston nor rings?

I'm afraid that when I was instructed to be specific in the title of my post, I kind of said it all... Here is the issue:

I have a 2001 Isuzu Rodeo. It has been going through excessive amounts of oil. No blue smoke, no drips whatsoever.

Through an Isuzu forum I find this is a common problem for model years up to and including mine as oil drain holes for the cylinders that were made in the pistons clog with carbon.

In that the vehicle is a 2001, I can well suspect those little holes are well caked and packed.

Though some folks state that they remove the spark plugs, pour a commercial internal auto engine cleaner called B12 into the cylinders and allow an over-nite soak, other auto-techs state that the only way to clear the drain holes is to tear apart the engine and drill the holes in the pistons out or replace them altogether.

Is there a chemical that will eat away and dissolve the carbon whereas after allowing whatever sufficient soak time is suggested I could then change the oil and have a hope for cleared out ports without damage to the metal engine parts?

• I don't think that's possible. Carbon is pretty durable. In fact, it is much easier to dissolve the whole engine while keeping the carbon. Dec 28, 2017 at 21:44

If it's pure carbon, then the only way to remove it I can think of is by rigorous oxidation (e.g. by burning in oxygen flow or by reaction with strong oxidants (e.g. conc. $\ce{H2SO4}$, $\ce{HNO3}$)), but this is going to damage the metal parts either, as Ivan said.