Toyota Pick-ups/Land Cruiser/4Runner 1970-1988



There are three sources of automotive pollutants; crankcase fumes, exhaust gases, and gasoline evaporation. The pollutants formed from these substances fall into three categories: unburned hydrocarbons (HC), carbon monoxide (C), and oxides of nitrogen (NOx). The equipment used to limit these pollutants is called emission control equipment.

Due to varying state, federal, and provincial regulations, specific emission control equipment have been devised for each. The U.S. emission equipment is divided into two categories: California and 49 State (Federal). In this section, the term "California" applies only to trucks originally built to be sold in California. California emissions equipment is generally not shared with equipment installed on trucks built to be sold in the other 49 States. Models built to be sold in Canada also have specific emissions equipment, although in most years 49 State and Canadian equipment is the same.

The following abbreviations are used in this section:

AAP: Auxiliary Acceleration Pump
ABV: Air By-Pass Valve
AI: Air Injection
ASV: Air Switching Valve
BVSV: Bi-Metal Vacuum Switching Valve
C: Carbon
CB: Choke Breaker
CCo: Catalytic Converter
CO: Carbon Monoxide
CO 2 : Carbon Dioxide
DP: Dashpot
EACV: Electronic Air Control Valve
EGR: Exhaust Gas Recirculation
EVAP: Fuel Evaporative Emission Control
H: Hydrogen
HAC: High Altitude Compensation
HAI: Hot Air Intake
HC: Hydrocarbon
HIC: Hot Idle Compensation
H 2 O: Water
MC: Mixture Control
N: Nitrogen
NOx: Nitrogen Oxides
PCV: Positive Crankcase Ventilation
SC: Spark Control
TP: Throttle Positioner
TVSV: Thermostatic Vacuum Transmitting Valve
VCV: Vacuum Control Valve
VSV: Vacuum Switching Valve
VTV: Vacuum Transmitting Valve