BMW 5251 Service Manual page 104

113-10
Cylinder Head Removal and Installation
4
Working above engine, disconnect the following:
Vent line from cylinder head cover (A).
.
Oxygen sensor connectors (B).
Electrical harness connector from VANOS solenoid
valve (C).
Electrical harness connectors at throttle valve position
switch (D), ASC valve position switch (E), fuel injector har-
ness (F) and vent valve (G).
CAUTION-
Be sure to mark oxygen sensor harness connectors so that
they can be reassembled correctly Do not interchange con-
nectors.
4
Where applicable, remove schraeder valve cap (arrow) from
air connection on fuel rail. Using a tire chuck, blow fuel back
through feed line using a brief burst of compressed air (max-
imum of 3 bar or 43.5 psi).
WARNING-
.
Fuel in fuel line is underpressure (approx. 3
-
5 bar or 45
-
75
psi) and may be expelled. Do not smoke or work near
heaters or other fire hazards. Keep a fire extinguisher
handy Before disconnecting fuel hoses, wrap a cloth
around fuel hoses to absorb any leaking fuel. Catch and
dispose of escaped fuel. Plug open fuel lines.
-
Always unscrew the fuel rank cap ro release pressure
; n the tank before working on the tank or lines.
Disconnect fuel lines by sliding locking collar in (arrows) and
pulling lines apart.
NOTE-
BMW uses three styles of fuel line connections; a one-time
use clamp; a locking fitting that uses BMWspecial tool 16 1
050 to release; and a quick release sleeve (above) that dis-
connects the line when depressed.