I had my 4d56 tested kanina. Hehe ala ako magawa so tiningnan ko kung papasa siya (july pa ako due for registration by the way). Here's a list of what i did:

1. Cleaned my air filter
2. Cleaned my muffler/exhaust via "gripo"

Ang passing rate po for a normally aspirated engine (diesel) ay 2.5. But for new vehilces as of january 2003, 1.2 po ang passing. My engine got a high .88!

Subukan po muna ninyo ipatest..lets not cheat on the process. :wink: