Inspection Items

No-load rapid-acceleration exhaust smoke density test:
The testing and sampling must start in 5-6 seconds after the deposit material is removed. When the test starts, step on the gas pedal hard for 4 seconds, release the pedal, and return the engine back to idle for 11 seconds, thus completing a test cycle (15 seconds). The sample is taken at the beginning of every cycle when the pedal is pushed. Repeat the test cycle 3 times until the difference between the smoke density readings is within 3% (level of pollution). ----- (A)
Full-load constant-rpm exhaust smoke density test:
Push the gas pedal to the very end. Set the following 3 test points according to the maximum rated horsepower of the engine. Select the proper gear for testing in sequence.
1. The level of pollution at 100% of that rpm ± 50rpm ----- (B)
2. The level of pollution at 60% of that rpm ± 50rpm ----- (C)
3. The level of pollution at 40% of that rpm ± 50rpm ----- (D)

If any of the level of pollution at the 4 testing points mentioned above fails to comply with the legal criteria (50% for vehicles made before Jun 30 1993, 40% for vehicles made between Jul 1 1993 and Jun 30 1999, 35% for vehicles made after Jul 1 1999), the vehicle tested is considered failing the exhaust test, and a ticket will be given on site.