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1977 Volvo 242 244 245
Ignition wiring
The ignition system consists of a primary and secondary system. The secondary systems are the high
tension leads connecting the distributor cap with the spark plugs and the coil.
These wires should be inspected at each engine tune-up, and should be replaced if cracked, frayed or
damaged from abrasion. It is important to clean all parts of this secondary system thoroughly because
dirt greatly reduces the available voltage to the spark plugs.
Distributor cap and rotor
Check the distributor cap and rotor for cracks, carbon formation, dirt and erosion.
Timing Delay Valve
This valve should be replaced every 30,000 miles. A clogged valve will impair fuel economy.
pg. 53 Emission control systems
IV Engine Crankcase Ventilation System
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.
Cleaning PCV valve
The calibrated positive crankcase ventilation (PCV) valve should be removed and cleaned every 15,000
miles. Rubber hoses should be checked for damage at the same time. Replace if necessary.
V Engine External Exhaust Emissions
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