BAR SMOG CHECK GASOLINE
VISIBLE SMOKE TEST TRAINING
QUESTIONS AND ANSWERS WITH
COMPLETE SOLUTIONS 100%
CORRECT!!!
1. Timeline of the Visible Smoke Test
Incorporation (March 2008): The Visible Smoke Test was officially
incorporated into the Smog Check program to address vehicles emitting
excessive smoke, which is a clear indicator of poor engine maintenance or
internal failure, even if the vehicle might otherwise "pass" a tailpipe sniffer
test.
Revision / "BAR Snap Test" (January 2010): The procedure was refined
to include the standardized "BAR Snap Test" sequence. This specific,
high-intensity throttle snap protocol was introduced to provide a consistent,
repeatable method for inducing and observing smoke emissions under load-
like conditions.
2. Applicability of the BAR Snap Test
Q: To which cars does the BAR Snap Test apply? A: All model years and
Gross Vehicle Weight Ratings (GVWR) of gasoline, CNG, LPG, and ethanol
vehicles subject to a Smog Check.
Explanation: The test is broadly applied because any internal combustion
engine fueled by these substances can produce visible smoke if the engine,
fueling, or emission control systems are compromised.
Procedure: The technician must observe the tailpipe exhaust plume during
the idle test, the crankcase (PCV) test, and the series of three throttle snaps.
Compressed Natural Gas -ANSWER ✔✔CNG
VISIBLE SMOKE TEST TRAINING
QUESTIONS AND ANSWERS WITH
COMPLETE SOLUTIONS 100%
CORRECT!!!
1. Timeline of the Visible Smoke Test
Incorporation (March 2008): The Visible Smoke Test was officially
incorporated into the Smog Check program to address vehicles emitting
excessive smoke, which is a clear indicator of poor engine maintenance or
internal failure, even if the vehicle might otherwise "pass" a tailpipe sniffer
test.
Revision / "BAR Snap Test" (January 2010): The procedure was refined
to include the standardized "BAR Snap Test" sequence. This specific,
high-intensity throttle snap protocol was introduced to provide a consistent,
repeatable method for inducing and observing smoke emissions under load-
like conditions.
2. Applicability of the BAR Snap Test
Q: To which cars does the BAR Snap Test apply? A: All model years and
Gross Vehicle Weight Ratings (GVWR) of gasoline, CNG, LPG, and ethanol
vehicles subject to a Smog Check.
Explanation: The test is broadly applied because any internal combustion
engine fueled by these substances can produce visible smoke if the engine,
fueling, or emission control systems are compromised.
Procedure: The technician must observe the tailpipe exhaust plume during
the idle test, the crankcase (PCV) test, and the series of three throttle snaps.
Compressed Natural Gas -ANSWER ✔✔CNG
