Volvo 1997 850 Manuel D’Utilisation

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1997 Volvo 850
 
Unstable idle, misfiring, or poor emission control is often caused by leaking vacuum hoses or 
connections. Check all vacuum hoses and connections. 
 
Idle air control system 
 
Your Volvo is equipped with an electronically controlled idle air control system that requires no 
checking or adjustment. 
 
Timing belt 
 
For proper functioning of the vehicle and its emission control systems, Volvo recommends that the 
timing belt be replaced every 70,000 miles (112,000 km). 
 
Fuel system cap, tank and lines and connections 
 
The effectiveness of the fuel system to contain hydrocarbons is dependent largely on a leak-free system. 
Check for proper sealing of the gasoline filler cap which contains "O" ring type seals. 
 
Fuel (line) filter 
 
The fuel line filter is located next to the fuel pump. For proper functioning of the vehicle and its 
emission control systems, the fuel line filter should be replaced at 100,000 miles (160,000 km). The 
filter is replaced as one complete unit. Replace more frequently if contaminated fuel is introduced into 
the tank (or if there is reason to suspect that this has occurred). 
 
Charge air cooler (Intercooler) 
 
Turbo-charged engines employs a turbo-compressor to force air into the engine inlet manifold and a 
charge air cooler to cool the compressed inlet air. The resulting increase in air flow raises pressure in the 
intake manifold by approx. 8.7 psi (over atmospheric pressure) and engine power output by approx. 50 
horsepower over that developed by the normally-aspirated engine. The charge air cooler (which 
resembles a radiator) is located between the turbo-compressor and inlet manifold. 
file:///K|/ownersdocs/1997/1997_850/97850_806.htm (3 of 10)12/30/2006 10:14:29 AM