Which is better, Ovi air-fuel ratio regulator or combustion chamber foam cleaner?

Combustion chamber foam cleaning agent is good.

At present, combustion chamber foam cleaning agents (Anceaux, 3M, Li Baozi, etc. ) what is sold in the market can be roughly divided into two ways of use. One is to remove the air filter and inject it from the throttle; The other is to remove the cheating nozzle or spark plug and spray it directly into the cylinder.

Both air-fuel ratio regulator and combustion chamber foam cleaner can remove carbon deposit and restore compression ratio, thus prolonging engine life. But the latter is relatively more affordable and worth trying by consumers.