check engine light VOLVO V4 2003 User Guide

WARNING!
The coolant fan may start or continue to operate (for up to 6 minutes) after the engine has been switched off.
pg. 112 Fuel/emissions systems
Fuel system
The fuel system is all-electronic and is microprocessor-controlled. It can continually compensate for variation in
engine load, speed and temperature to give the best economy and power. A mass air flow sensor measures the inducted
air. In this way the system can make instantaneous adjustments for changes in air temperature or density, thus always
assuring the best economy with the lowest possible exhaust emissions.
Heated oxygen sensor
This is an emission control system designed to reduce emissions and improve fuel economy. The heated oxygen sensor
monitors the composition of the exhaust gases leaving the engine. The exhaust gas analysis is fed into an electronic
module. This adjusts the air-fuel ratio to provide optimum conditions for combustion and efficient reduction of the
three major pollutants (hydrocarbons, carbon monoxide and oxides of nitrogen (NOx)) by a three-way catalytic
converter.
Crankcase ventilation
The engine is provided with positive crankcase ventilation which prevents crankcase gases from being released into the
atmosphere. Instead, the crankcase gases are admitted to the intake manifold and cylinders.
Evaporative control system
The car is equipped with an evaporative control system which prevents gasoline vapor from being released into the
atmosphere.
The system consists of a fuel tank with filler pipe and cap, a rollover valve, a Fill Limit Vent Valve (FLVV), vapor
vent lines, a charcoal canister, a purge line, a purge control valve and engine connections. In addition, there is a
pressure sensor connected to the fuel tank and a filter -protected Canister Close Valve (CCV) on the atmospheric side
of the canister, for system diagnosis.
The gasoline vapor is channeled through the rollover valve and the FLVV via the vapor vent lines into the charcoal
canister, where it is stored. When the engine is started, the gasoline vapor is drawn from the charcoal canister to the
engine's air intake system and into the combustion process.
NOTE:
If the fuel filler cap is not closed tightly or if the engine is running when the car is refueled, the Check Engine light
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Bulb failure warning22
Bulbs126
C
Cabin air filter35
Capacities125
Center head restraint3
Central locking switch42
Chains - winter driving81
Changing a wheel87
Child booster cushion11
Child Restraint Anchorages14
Child safety15
Child safety locks - rear doors49
Concealed storage bin (wagon)59
Coolant - checking/changing117
Cooling system68,124
Cruise control31
D
Daytime Running Lights23
Detachable trailer hitch - installing76
Detachable trailer hitch - removing77
Dimensions127
Doors and locks42
Drive belt117
Driving economy64
Dynamic Stability Assistance (DSA)30
E
EBD74
ECC - Electronic Climate Control36,37
Electrical outlet33
Electrical system69,126
Electrically operated driver's seat50
Electrically operated front seats48
Emergency towing70
Emergency warning flashers26
Emissions systems112
Engine123
Engine air filter110
Engine compartment111
Engine oil115,122
Engine oil - checking/changing114
F
Fog light - rear24
Fog lights24
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