Honda Bmw 5 Service Manual

							
Fuel Injection 
CAUTION- 
Be sure  ignition  is OFF before disconnecting  or reconnecting 
DME system  components. 
Remove  engine coolant temperature  sensor: 
Unclip crankcase  vent hose 
(C) from  cylinder head  cover. 
Remove  plastic cover 
(6) from atop intake manifold run- 
ners. 
Working  under front  of intake manifold,  disconnect ECT 
harness. 
Unscrew  ECT sensor 
(C) from cylinder head. 
Installation  is reverse  of removal: 
Use  new  copper sealing  washers when installing sensor. 
Replace  any engine  coolant lost. 
Tightening torque 
Temperature sensor  to cylinder  head 
13 Nm (10 it-lb) 
Intake air temperature ([AT) sensor, 
testing and replacing 
4 The  intake  air temperature  (IAT) sensor (arrow) signal  is 
used  by the  ECM  to monitor  intake air temperature  for fuel 
and 
igntion adaptation. The  sensor is .ocared in rne  ntane 
man:lold behind the throttle housng. 
The  ECM  monitors an applied voltage (5 vdc) to the  sensor 
The  voltage drop  across the sensor varies as the intake  air 
temperature (sensor resistance)  changes. 
NOJE- 
The IATsensor is an NTC (negative temperature coefficient) 
type sensor.  In other  words,  as the temperature  rises, resis- 
tance  through the sensor  decreases. 
If  the  IAT sensor input is  implausible, a 
fault code is set.The 
MIL is illuminated  when OED II fault criteria are exceeded. 
The  ECM then  operates the  engine using only  the engine 
coolant  temperature (ECT)  sensor input. 
The intake air temperature  sensor can be tested using a 
mul- 
timeter across its terminals: 
/ IAT sensor  resistance @ 20 C (68°F) / 2.2 - 2.7 lkCk 
~ -- ~~ - 
CAUTION-- 
Be  sure ignition  is 
OFFbefore disconnecting  or reconnecting 
DME system  components.   
						

							
130-1 2 
Fuel Injection 
- Disconnect intake air boot from throttle housing. Unbolt throt- 
tle  housing and  lay aside.  It is not  necessary  to disconnect 
throttle cable or electrical harness connectors from throttle  housing. 
- Remove  electrical harness  connector from IAT sensor. 
- Unclip temperature sensor and  remove from intake manifold. 
- Installation  is reverse  of removal.  Use a new  gasket  at throttle 
housing. 
Throttle position  sensor (TPS), 
testing and replacing 
4 The throttle position sensor (arrow) is located  on top  of the 
throttle  valve housing and  provides the ECM  with a voltage 
value that  represents  throttle position  (angle) and rate of 
movement. 
TheTPS is  non-adjustable.  If the throttle position sensor is re- 
placed, the previous learned  TPS settings  must be cleared 
from the ECM using  a BMW-compatible  scan tool. 
If the throttle position sensor  signal is defective,  afault code is 
stored  and the 
MILis illuminated when OBD II fault criteria are 
exceeded.  The ECM still operates  the engine using the  mass 
air  flow 
(MAF) sensor  and engine rpm inputs. 
- Check  throttle position sensor function  by disconnecting  har- 
ness  connector  and checking  continuity  across terminals.  If 
test results are incorrect, 
replace throttle position  sensor. The 
sensor is  non-adjustable. 
Throttle 
~osition sensor testina  values - 
Terminals  Test 
values 
1 and ground in harness 5 vdc (approx.) 
connector, ltey  on 
1 and 3 at sensor  4.0 itR(appr0x.) 
1 and 2 at sensor Throttle 
plate rotated  from idle to 
lull  throttle,  continuously variable 
from  1.0 
- 4.0 1tR 
CAUTION- 
Be sure  ignition  is OFF before disconnecting  or reconnecting 
DME svstem components. r   
						

							
130-1 3 
Fuel Injection I 
< Unplug harness  connector (arrow) from sensor. 
CAUTION- 
Be sure ignition  is OFF before disconnecting  or reconnecting 
DME  system  components. 
NOTE- 
Do not  confuse  the throttle  position  sensor on  the main Nirot- 
tle body  with the throttle  position  switch on the  secondary 
throttle  body, where applicable. 
- Remove two  mounting screws holding sensor to throttle 
housing. 
- Installation  is reverse  of removal. Clear adaptation settings 
from  ECM  using BMW-compatible scan tool. 
NOTE- 
Poor idle quality  may be noticeable  for a period  if the adapta- 
tion settings  are not cleared  after installing  new TPS. 
ldle speed control  valve, 
checking and replacing 
The  idle speed  control valve regulates idle  speed by redirect- 
inq airaround  the throttlevalve.The idlespeed control valve is 
mounted  on the underside  of the intake  manifold adjacent to 
the  dipstick  tube bracket. Accessing the valve  is best  accom- 
plished  by first removing the  air filter housing  and the throttle 
body assembly. 
The  valve  issupplied  with 
batteryvoltagefrom the ECM  relay. 
The idle speed control  valve incorporates a two-coil rotary ac- 
tuator.  The ground  sides of each  coil are pulsed 
sirnulta- 
neously by  the ECM.  The duty cycle  of each circuit is varied to 
achieve  the required  idle speed. 
Afaulty  ldle speed control  valve sets afault code and the MIL 
is  illuminated  when 
OED II fault criteria  are exceeded. 
Before checking the  idle speed control valve,  confirm that the 
throttle  position  sensor is working correctly. 
- With engine  running, check that idle speed control  valve is 
buzzing. 
- Turn  on AIC system  or shift transmission into  drive. ldle 
should  remain steady  or increase  slightly.   
						

							
Fuel Injection 
- If idle speed  valve is not buzzing, or  if idle  decreases  when 
AIC is turned  on, stop engine and disconnect  harness  con- 
nector from idle speed  valve. 
connector 
CAUTION- 
Be  sure ignition  is OFFbefore disconnecting  or reconnecting 
DME system  components. 
Checlc resistance  of valve across valve terminals. 
Idle speed  control  valve resistance 
Terminals 
1 and 2 20 i-2Q 
Terminals 2 and 3 20 C2Q 
Terminals 1 and 3 40 C4Q 
The  idle speed control  valve is mounted under the intake 
manifold. Accessing  the valve is best accomplished by  first 
removing  the air filter  housing  and the throttle  housing. 
< Disconnect intake air boot from throttle housing. Unbolt throt- 
tle  body  and lay aside.  Do not disconnect throttle  cable or 
electrical  harness connectors to throttle  body. 
NOTE- 
For additional worlcing room,  unfasten  and lift out  the com. 
plete air  filter housing. 
- Working under intake manifold, disconnect electrical  harness 
connector from  idle speed control valve. 
Unbolt dipstick tube 
bracket (A) from  intalte manifold. 
- Remove  two bolts (B) retaining idle speed control  valve to un- 
derside of  intalte manifold. Remove valve  from intalte  mani- 
fold.  Remove hose  clamp and disconnect hose. 
- Installation is reverse  of removal.  Use new gaskets when  in- 
stalling.   
						

							
Fuel injectors, checking and replacing 
The fuel injectors  are electronically controlled solenoid valves 
that  provide precisely  metered and atomized fuel into the en- 
gine intake ports. 
The  injectors receive voltage from the ECM relay.  The ECM 
controls  the opening  by activating  the ground circuit 
forthe in- 
jector valve solenoids.  The ECM varies  the duration  (in milli- 
seconds)  of opening  time to regulate  the 
airlfuel ratio. 
For  a quick 
check of the  injectors, run  the engine and touch 
each injector with a screwdriver or stethoscope. You should 
feel a vibration  or hear a buzzing 
Remove fuel injection harness  from injectors  by unclipping 
locking clip  at each injector.  Lift harness  off injectors. 
CA U JIOG 
Be sure ignition  is OFF before disconnecting  or reconnecting 
DME system  components. 
Use  a multimeter  to test injector  coil resistance between in- 
jector  terminals. 
l~uel injector  coil resistance 16R at 20 C (68 F) 
Disconnect negative 
(-) battery cable 
CAUTIOG 
Prior to disconnecting  the battery, read the battery  discon- 
nection cautionsgiven 
in 001 General  Warnings and  Cau- 
tions. 
4 Remove plastic trim  plugs (arrows)  and fasteners, then re. 
move cover from  above fuel injectors. 
- Disconnect vacuum line  from fuel pressure  regulator. 
- Remove wiring harness duct mounting fasteners.   
						

							
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.   
						

							
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.   
						

							
130-1 8 
1 Fuel injection Secondary air injection 
1. Secondary air pump  (in right 
front  wheel  housing) 
2. Secondary  air vacuum  vent 
valve  solenoid  (on intake mani- 
fold) 
3. Secondary  air check valve 
4. Intake manifold 
5. Exhaust  manifolds 
6. Diverter valve (at exhaust mani- 
fold) 
Engine control module (ECM), 
removing and installing 
The  ECM uses  stored functions and processing programs to 
process the input signals  from the sensors. These input sig- 
nals are used to calculate  the control (output) signals to  the 
actuators 
(e.g., ignition coils, injectors). 
NOTE- 
Consult  an authorized BMW dealer before replacing the 
ECM. 
- Disconnect negative (-) battery cable.  Wait approximately 
one  minute. 
Prior  to disconnecting  the 
battely, read the battery  discon- 
nection cautions  in 
001 General Warnings  and Cautions. 
Access engine control  module (ECM): 
Release interior ventilation filter  cover latch 
(A) and re- 
move  cover. 
Release plastic locking  tab 
(B). 
Rotate air duct inward (arrow) to unloclc from bulk head 
and  remove duct. 
Release spring  lock 
(C) to remove  lower filter  housing. 
Slide filter housing  away from inner  fender  to  remove. 
- Remove electrical  box (E-box)  cover fasteners  and remove 
cover. 
- If  testing  ECM or  connected  components, use breakout  box 
to  allow tests  to be  made with  connector attached  to the 
ECM.  This prevents  damage to small terminals in  connector.   
						

							
Fuel Injection I 
- As an alternative,  harness connector  housing can be sepa- 
rated so that electrical 
checlts can be  made from backof con- 
nector. 
4 If replacing ECM, disconnect control module harness  con- 
nector  (arrow)  by releasing fastener  and pivoting connector 
up  and 
off ECM. 
CAUTION- 
Be sure ignition  is OFF before disconnecting  or reconnecting 
DME system  components. 
- Remove  ECM from retaining brackets  and lift off holder. 
- Installation is  reverse of removal. 
- Before attempting  to start  engine,  use BMW  service  tester 
DISplus, MoDiC, GTI or equivalent: 
- Code  replacement ECM  with application  information (i.e. 
engine code, transmission  type,  etc.). 
Align  ECM to EWS  (electronic  immobilizer). 
Siemens MS 41.1 ECM pin assignments 
ECM  pin assignments  are given in Table b. For  engine  man- 
agement system  schematics, see ELE  Electrical Wiring 
Di- 
agrams. 
CAUTION- 
a Always  wait at least  one minute after turning  off the  ignition 
before removing  the connector  from the 
ECM. If the  con- 
nector  is removed before  this time,  residual  power 
in the 
system relay  may damage  the 
ECM. 
Always connect  or disconnect  the control module  con- 
nector  and meter  probes  with the  ignition 
off 
When malting checks  at the ECM  itself, a breakout  box 
should  be used  to allow tests to be  made with the  connector 
attached  to the  ECM.  This also prevents damage  to the  small 
terminals  in the connector.  As an alternative, the harness 
connector housing  can be separated  so that electrical checlts 
can  be made from  the back  of the  connector. 
Table  b. Siemens  MS 
41.1 ECM pin assignments 
Pin 
1 
2 
3 
4 
Signal 
output 
output 
output 
qround Componenfffunction 
Ignition coil control, cyl. 2 
Ignition coil control, cyl. 4 
ignition coil control,  cyl. 6 
Ground  Notes 
Primary signal, 
ignition 
coil 2 
Primary signal, ignition coil 4 
Primary signal,  ignition coil 6 
Ground   
						

							
I Fuel Injection 
Table b. Siemens MS 41.1 ECM pin  assignments (continued) 
Pin 
l~iqnal I Componentlfunction 1 Notes I - I I 
5 loutput I Fuel injector control, cyl. 2 I Pulsed ground (pulse width in ms),  cyl. 2 I I I 
6 loutput /Fuel injector control, cyi. 1 I Pulsed ground (pulse width in ms), cyl. 1 
I I I 
14 linput I Intake air temp.  sensor (IAT) I Intake air temperature signal 
- 7 
8 
9 
10 
11 
12 
13 
ground 
input 
output 
input 
input 
15 
16 
17  18 
19 
20 
21 
22 
I - I I 
35 loutput /Secondary  air injection ISecondary air inj. pump relay control 
25 
26 
27 
28 
29 
30 
31 
32 
33 
36 
/output I Engine speed output IEngine speed signal 
Mass air flow sensor 
Mass air flow sensor 
instrument cluster 
Engine coolant 
temp. 
(ECT) sensor 
Not used 
Throttle  position sensor  (TPS) 
Not used 
input 
input 
input 
input 
output 
output 
out~ut 
37 1 - /Not  used I 
Mass air flow sensor signal 
Mass air flow sensor signal 
Fuel consumption signal 
ECT  signal 
Throttle  position signal 
ground 
input 
output 
ground 
output 
output 
output 
ground 
output 
Traction control (rear engine speed signal)  Automatic climate control 
Not used Electronic immobilizer control (EWS) 
Auto.  climate control 
(AIC on input) 
instrument 
cluster 
Camshaft actuator control  (VANOS) 
Fuel iniector control,  cvl. 
3 
AES/ASC module 
Automatic climate control  instrument cluster (CARE signal) 
Camshaft actuator  (VANOS), switched ground 
Pulsed ground (pulse width  in 
ms), cyl. 3 
Oxygen sensor heater (no. 1 in front  of catalytic 
converter) 
Power  supply  (terminal 
30) 
Idle speed control valve 
Ground 
Ignition coil control, cyl. 
1 
Ignition coil control, cyl. 3 
Ignition coil control, cyl. 5 
Ground Fuel injector control,  cyl. 
5 
Oxygen sensor heater ground 
Battery voltage 
(E+) at  all times 
Pulsed ground-open signal  (See pin 
53) 
Ground 
Primary signal, ignition coil 
1 
Primary signal, ignition coil 3 
Primary signal, ignition coil 5 
Ground 
Pulsed ground (pulse width  in ms),  cyl 
5