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Cylinder Head Removal and Installation
- Install exhaust manifolds using new gaskets and nuts. Coat
manifold studs with copper paste prior to installing nuts.
Tightening torque Exhaust
maniiold to cylinder head (M7)
20 Nm (15 ft-lb)
- Install electrical harness connectors for oil pressure sender
and coolant temperature sensor before installing
intalte man-
ifold.
7 Install intake manifold:
1. Manifold mounting nuts: tighten to 15 Nm (1 1 ft-lb)
2. Fuel pipe bracltet
3. Fuel pipe bracltet
4. Vacuum pump bracltet
5. Manifold mounting bracltet
6.
Tank venting valve bracltet
7. Mounting bracket to manifold bolt (M6)
8. Mounting bracket to cylinder block nut (MIO), tighten to
47 Nm (33 fi-lb)
Intake manifold installation is reverse of removal, noting the
following:
* Use new fuel injector seals.
Carefully
check intake manifold gasket and replace if nec-
essary.
Inspect O-ring seal between mass air flow sensor and air
filter housing. To facilitate reassembly, coat seal with
acid-
free grease.
Use new fuel injector seals.
Carefully check intake manifold gasket and replace if
necessary.
CA UTIOPI-
When reattaching throttle assembly harness connector, con-
nector is fully tightened when arrows on connector
andplug
line up.
Tightening torque
lntalte manifold to cylinder
head (M7)
15 Nm (1 1 it-lb) ~ ~- Mounting bracket to cylinder bloclt (M10) 47 Nm (33 ft-lb)
Mounting bracket to intake manifold (MI?) 10 Nm (89 in-lb)
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1 13-60
Cylinder Head Removal and Installation
Label and disconnect fuel lines from fuel rail by pressing lock-
ing sleeves
(arrows) in to release lines.
NOTE-
BMW uses three styles of fuel line connections; a single use
clamp; a locking fitting that uses special tool
16 1 050 to re-
lease; and a quick release sleeve
(arrow) that disconnects
the line when depressed.
CAUTION-
Fuel may be expelled under pressure. Do not smoke or
work near heaters or other fire hazards. Keep a fire
exfin-
guisher handy Before disconnecting fuel hoses, wrap a
cloth around fuel hoses to absorb
leaking fuel. Plug all
I ooen fuel lines. I
Always unscrew fuel tank cap to release pressure in
tank before
removinq fuel lines.
Cap fuel lines and fuel rail inlets.
Disconnect vacuum lines
(A, B and C) from rear of intake
manifold.
Working at rear of intake manifold, disconnect crankcase
ventilation valve from pipe by prying up on lock
(A) and slid-
ing tube forward
(B).
Page 307 of 1002
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Camshaft Timing chain1
< Remove Automatic Stability Control (ASC) throttle body:
Disconnect electrical harness from throttle position sensor.
Disconnect ASC actuator cable (arrow).
Remove
3 mounting fasteners and remove throttle body.
4 Disconnect fuel tank vent valve line and cap off line (arrow).
- Drain engine coolant and remove hoses from thermostat
housing. See
170 Radiator and Cooling System.
- Remove water pump and thermostat housing. See 170 Ra-
diator and Cooling System.
- Remove left side upper timing chain cover retaining bolts and
remove cover.
4 Counter hold right intake camshaft
CAUTION-
Counter hold camshaft with a 27mm open-end wrench while
loosening sprocket bolts. Grind wrench if necessary to pre-
vent damage to head.
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130-6
Fuel Injection
Fuel supply to the injection system is provided by a high pres-
sure electric pump mounted inside the fuel tank. The pump is
powered via the fuel pump relay. If the relay is faulty, the fuel
pump will not run and the engine will not start.
NOTE-
* Fuel delivery volume and fuel pressure are critical to prop-
er operation. Fuel pressure direcfly influences fuel deliv-
ery
Fuel pump relay, fuel pressure and fuel volume tests are
given in 160 Fuel Tank and Fuel Pump.
Relieving system fuel pressure
The fuel system retains fuel pressure in the system when the
engine is off. To prevent fuel from spraying on a hot engine,
system fuel pressure should be relieved beforedisconnecting
fuel lines. One method is to tightly wrap
ashop towel around a
fuel line fitting and loosen or disconnect the fitting. Cleanli-
ness is essential when working with fuel components. Thor-
oughly clean the unions before disconnecting fuel lines.
When system faults are detected, a diagnostic trouble code
(DTC) is stored in the engine control module (ECM). The MIL
also iiluminates if an emissions-related fault is detected
When faults arise, or if the malfunction indicator lamp (MIL) is
illuminated, begin troubleshooting by connecting BMW ser-
vice tester
DISplus. MoDiC, GTI or equivalent scan tool. The
capabilities of OBD
II software has the potential to save hours
of diagnostic time and to help avoid incorrect component re-
placement and possible damage to system components.
CAUTION-
- The tests in this section may set fault codes (DTCs) in the
ECM and illuminate the
MIL. Affer all testing is completed,
access and clear DJC fault memory using an
OED I1 or
BMW compatible scan tool. See OBD On-Board Diag-
nostics.
0 Only use a digital multimeter for electrical tests.
. Relay positions can vary Be sure to confirm relay posi-
tion by identifying the wiring in the socket using the wir-
ing diagrams found in ELE Electrical Wiring
Diagrams.
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I Fuel Injection
Release injector locking clips at each injector and pry injector
wiring duct up off injectors.
Clamp off fuel supply line and fuel return line at end of fuel
rail. Disconnect fuel supply fuel return lines from fuel rail.
WARNING -
Clamp off the fuel lines and then wrap a clean shop towel
around the lines before removing them. Residual
fuelpres-
sure is present in the lines.
Fuel is discharged. Do not disconnect any wires that
could cause electrical
sparks. Do not smoke or work
near heaters or other fire hazards. Keep an approved
I fire extinguisher handy. I
- Remove fuel rail mounting fasteners
- Pull up on fuel rail and remove individual injectors by remov-
ing injector retaining clip and pulling injector from rail.
- Installation is reverse of removal. Fit new O-rings when in-
stalling injectors. For ease of installation, lightly lubricate in-
jector O-ring with
SAE9O gear lube.
Tightening torque Fuel rail to
intake manifold 10 Nm (89 in-lb)
Evaporative emissions, overview
On E39 MS 41 .I cars, the evaporative emissions system is
combined with the tank ventilation system. The evaporative
system is monitored by the ECM for correct purge operation
and leak detection.
The carbon (purge) canister is purged using engine vacuum
via the
purgevalve.The purgevalve (located nextto the mass
airflow sensor) is ECM controlled and regulates the purge
flow into the intake manifold. The valve is powered open and
closed by an internal spring.
If the evaporative emission valve circuit is faulty, a fault code
is set and the MIL is illuminated when OBD
II fault criteria are
exceeded. If the valve is mechanically faulty, poor driveability
may result and a mixture adaptation fault is stored in the
ECM.
The leak diagnosis pump (LDP) is activated by the ECM and
pressurizes the fuel tank and evaporative system as apart of
theOED I1 leakdetection monitor. If the LDP orthe LDP circuit
is defective, afault code is set and the MIL is illuminated when
OBD
I1 fault criteria are exceeded. The LDP is mounted the
left rear wheel well behind the fender liner.
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Fuel Injection 1
NOTE-
The 1998 5281' with MS 41.1 requires a barometric pressure
sensor input signal for activation of the
LDP check. This sen-
sor is located on the passenger side strut tower
fo~lard of
ABS/ASC hydraulic unit.
Evaporative emissions
1. ECM
2. Purge valve
3. Leak detection pump (LDP) (in
lefl rear wheel housing)
4. Filter
5. Liquid vapor separator
6. Purge canister
7. Fuel tank
Secondary air injection, overview
The secondary air system pumps ambient air into the exhaust
stream afler a cold engine start to reduce the warm up time of
the catalytic converters and to reduces HC and CO emis-
sions. The ECM controls and monitors the secondary air in-
jection system. The secondary air pump operates at a start
temperature of between 10°C (50°F) and 40°C (104°F) and
continues to operate for a maximum of
2 minutes at idle
speed.
The electric air pump draws in ambient air and supplies it to
the divertervalve. The vacuum ventvalve (solenoid) switches
vacuum to open the divertervalve when activated by the
ECM. Once opened, the diverter valve allows air to be
pumped into the exhaust stream.
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/Fuel Injection
4 Remove dipstick guide tube:
Disconnect wiring harness brackets from tube (A).
Unclip fuel lines from dipstick tube
(El).
Remove lower guide tube mounting bolt (C). Pull out dip-
stick guide tube.
< If necessary, disconnect electrical harness connector at fuel
tank venting valve (A). Disconnect hose at quick disconnect
fitting (arrow).
Working at throttle housing, turn harness plug counterclock-
wise and disconnect. Remove throttle assembly mounting
fasteners (arrows) and pull assembly off manifold.
Installation is reverse of removal
Replace sealing ring between throttle assembly and intake
manifold.
0 Reattach throttle assembly harness connector with care.
Arrow on fully tightened connector must line up with corre-
sponding arrow on throttle assembly housing.
* Connect BMW test equipment or equivalent and carry out
throttle plate adaptation following the on-screen directions.
Reattach throttle cable and check cable adjustment as de-
scribed under Throttle cable, adjusting
(MS 42.0).
Page 427 of 1002
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-.
Fuel Injection 1
4 If necessary, disconnect electrical harness connector at fuel
tank venting valve (A). Disconnect hose at quick disconnect
fitting
(arrow).
< Worlting at throttle housing, turn harness plug counterclock-
wise and disconnect. Remove throttle assembly mounting
fasteners
(arrows) and pull assembly off manifold.
- Installation is reverse of removal.
0 Replace sealing ring between throttle assembly and intake
manifold.
Reattach throttle assembly harness connector with care.
0 Arrow on fully tightened connector must line up with corre-
sponding arrow on throttle assembly housing.
- Use BMW scan tool to reset ECM adaptation values.