Diagnostic Technique
7-3
Air-Fuel Ratio Effects
Figure 7-1
contains some of the results possible when the air-fuel
ratio is sustained at conditions ranging from too lean to too rich.
Figure 7-1
: Air-Fuel Ratio Conditions and Results
CONDITION RESULTS
Too Lean Poor engine power
Misfiring at cruising speeds
Burned valves
Burned pistons
Scored cylinders
Spark knock or ping
Slightly Lean High gas mileage
Low exhaust emissions
Reduced engine power
Slight tendency to knock or ping
Stoichiometric Best all-around performance
Slightly Rich Maximum engine power
Higher emissions
Higher fuel consumption
Lower tendency to knock or ping
Too Rich Poor fuel mileage
Misfiring
Increases air pollution
Oil contamination
Black exhaust
Catalytic converter damage
To Next Page
Loading...