hi, i have a nissan datsun td23 pickup, last year hindi na register ng brother ko it failed the emission test. recently, i had the nozzles cleaned, timed the injection pump, clean the air filter and still have black smoke. the guys at the calibration center said that because its nissan maitim usok nyan. tama ba to?
That's not true. This is a clean burning engine, but emits more smoke than the newer engine models. A little black smoke is normal as long as it passes emission test.

ano pa ba pwede gawin para maipasa sa emission? (the mechanic recomended that we choke the pump on the day na mag pa emission.) but i want to do it legally clean para pagpalain tayo ni Lord. help...
You are doing the right thing. I have seen a lot of cars fail emission test. But when we tested it, the car was actually passing. This means that the testor may just want some under the table money for him to pass an already passing vehicle.