Thanks sa reply sir DD...
I brought my Monty sa casa and they performed SIQL on it. Wala naman daw na-detect na problem pero they heard the knocking sound with minor jerking ng engine after the test... When the engine revving has been released.

They checked the air filter and found it clean since it was just replaced 2 mos ago. The mechanic checked the connectors if ok too.

As a last step, they just hosed the exhaust with water to take out the carbon deposits

When I drove it home still theres some excessive white smoke. But as I used it the following day, even today the heavy smoking and knocking sound did not occur anymore.

Could the SIQL have corrected the setting of my injector or anything? What is SIQL?

Hopefully its really fixed now. Sana, but I doubt it. From experience, the problem may happen again if the the fault was not identified because the proper fix was not applied.