Honda Bmw 5 Service Manual

							
130-51 
Fuel Injection 
Oxygen sensors, checking 
The  oxygen  sensor provides  an input  voltage  signal [0.2 vdc 
(lean)  to 0.8  vdc  (rich)] to  the 
ECM based on  the oxygen  con- 
tent  in the  exhaust gas.  To generate  voltage, the  sensor tem- 
perature  must exceed 575 
F (300  C). Therefore  the sensor 
is  electrically  heated. 
NO  JE - 
The test given  below is not  a conclusive  test of oxygen  sen- 
sor efficiency  and does  not test how  the oxygen sensor re- 
acts to changing  conditions. Pin numbers and  wire colors 
can vary  Always check the  wiring diagrams to  confirm wire 
color  and pin assignment. 
0 The  oxygen  sensorconnectorplugs  are locatednext to the 
catalytic converters. 
With  connector  attached  to sensor, connect digital voltmeter 
between 
A and B wires  in connector. 
WARNING - 
Exhaust manifolds andpipes can be  hot enough  to cause se- 
rious burns.  Wear suitable  heavy gloves  and other  appropri- 
ate  protection. 
NOJE- 
Connector  style may vary  depending  on system  application. 
Consult wiring diagram  for system-specific  wiring. See 
ELE 
Electrical Wiring Diagrams. 
Start  engine. 
A fluctuating  voltage signal should  show on the 
meter. 
If voltage  is incorrect, turn engine  off and  check pre- 
heater  circuit  as described  below. 
NOJE- 
To check sensor  response to lean  and rich mixtures,  create 
an  air leak. 
Oxygen  sensor 
voltage at idle 
- Connect  digital voltmeterbetween  sensor heaterwires  (white 
wires, 
C and  D). Start engine  and check for battery  voltage. 
If  voltage  is not  present,  check oxygen sensor  heater fuses. 
0.2 to 0.8 vdc fluctuating 
NOJE- 
The  oxygen  sensor heater is powered  via fusedpositive (+) 
battery  voltage  and a switchedground  from the ECM.  See 
ELE  Electrical  Wiring Diagrams  for specific circuit informa- 
tion. 
- The  ground  side of the  oxygen sensor heater circuit  is pulsed 
on  and  off by the 
DME control  module.   
						

							
.. .- 
/Fuel lnjeciion 
NOJE- 
With engine oft disconnect harness connector  and checlc 
heating element resistance between white wires  on the  sen- 
sor  side  of harness.  If the element is electrically open  (no 
continuity), replace sensor. 
- If  oxygen sensor  does not produce  a fluctuating  voltage and 
preheater  circuit  is 
OK, replace sensor. 
NOJE- 
If not already applied, coat oxygen  sensor threads w~th anti- 
seize compound before installat~on. Do not  get  the com- 
pound on the  sensor tip. 
Tightening torque  Oxygen  sensor  to exhaust  system 
55 Nm (41 ft-lb) 
Fuel injectors, checking and replacing 
The fuel iniectors  are switched on  and off (oaened and 
closed) 
bythe ECM. The  injectors  are connkcted to acom- 
mon power  source. A ground signal from  the ECM is used to 
open  and close the  injectors. 
CA U JIOG 
Use only a digital multimeter or  an  LED injector  tester when 
testing injectors or  wiring. Use of an  analog 
VOM or incan- 
descent test light  may damaqe the engine  controlmodule. 
4 Remove fuel rail cover.  See 110 Engine  Removal  and  in- 
stallation. 
With  the engine running,  place the point  of a long screwdriver 
on  each  injector  and check  for a cliclting  vibration. 
If no vibra- 
tion  is  found  do the voltage 
checit shown below. 
Injector  electrical  loom  removal: 
- Loosen  mounting  nuts A. 
Remove  ground wire C. 
Disconnect  ignition  coil harness D   
						

							
Fuel Injection I 
4 Release spring  clips (arrows) from fuel injectors and  pull in- 
jector  electrical  loom straight  up to remove. 
4 Check that  ECM signal is present  at injector connectors. 
- Connect  digital voltmeter  to fuel injector harness plug. 
Operate  starter and 
check for voltage pulse. 
* Repeat for  each injector. 
- Remove fuel injectors by removing retaining clips 
- Installation is reverse  of removal: 
Fit new O-rings when installing injectors.  For ease  of instal- 
lation,  lightly lubricate  all fuel system O-rings with assem- 
bly lubricant. 
Check that  injector electrical connections are  correctly fit- 
ted and  that 
injectors are fully seated  prior to installing  iuel 
rail mounting bolts. 
Mass  air flow sensor  (MAF),  replacing 
The MAF sensor is provided  with operating power from  the 
ECM  relay.  Based on  calculated intake air mass,  the MAF 
generates 
avarying voltage (approx. 0.5 - 4.5 vdc)  as an  input 
signal to  the ECM. 
4 Remove  MAF sensor: 
Remove upper  air filter  housing locking clips. 
Unscrew and remove  MAF sensor harness 
(A). 
Disconnect intake air temperature sensor harness (B). 
Loosen  hose clamp (C). 
Remove upper filter  housing with sensor. 
- Installation is reverse  of removal   
						

							
130-54 
I Fuel Injection ldle speed control  valve, 
testing  and replacing 
ldle speed  is maintained  by the ECM through  the idle speed 
control  valve. The idle control function compensates  for en- 
gine load  and engine  operating conditions.  ldle speed is 
adaptive through  the ECM and  no adjustments  can be made. 
Before checking  valve, confirm that throttle position sensor  is 
working  correctly. 
NOTE- 
The test given  below  is an  electrical check  only. It does  not 
check the  mechanical  operation of the  valve.  If the  valve  is 
sticking, hanging up or is sluggish in operation,  substituting  a 
Inown good valve is the  best  way to  check it. 
With  engine  running, check  that idle speed  control valve  is 
buzzing. 
Turn  on 
AIC or shift  car into drive.  ldle should  remain steady 
or increase  slightly. 
If  valve  is not  buzzing, or if  idle decreases  in step above,  stop 
engine  and disconnect  harness connector from  valve. 
4 Check resistance of valve across its terminals.  Test values 
are  listed  below. 
ldle  speed  control  valve coil resistance 
Terminals 
1 and 2 20 +2% 
Terminals 2 and 3 20 +2Q 
Terminals 1 and 3 40 +4% 
NOTE- 
If you  suspect  an intermittent  fault, lightly  tap the  valve  while 
testing  resistance. 
With valve harness connector disconnected, check  for bat- 
tery voltage  at redlwhite  wire in connector with  ignition on. 
If . ~~ ~~ 
there is  no voltage, check  wiring between connector and 7 ECM relay.  See ELE Electrical  Wiring Diagrams. 
NOTE- - The idle speed  control  valve receivespositive (+) battery  volt- 
age  from  the ECM  (DME  main) relay   
						

							
Fuel Injection 
- If voltage is present as described  above, check wiring be- 
tween  ECM and valve.  If no  wiring  faults are found, check 
ECM signal  to valve. 
- When  replacing  idle speed  control valve, clean and  inspect 
all sealing  areas. 
. Inspect sealing ring  in throttle body and  replace if neces- 
sary. 
Throttle position sensor (TPS), 
testing and replacing 
The  throttle position sensor  (arrow) is mounted on the  side 
of  the  primary  throttle housing  and is directly  connected  to 
the  throttle  valve shaft.  The ECM  sends a voltage signal  to 
the potentiometer-type sensor and monitors the  voltage that 
comes  back. Resistance decreases  (voltage increases) as 
the throttle  opens. 
NOTE- 
Do not  confuse  the TPS on the  primary  throttle housing  with 
the throttle  switch on the 
ASC secondary  throttle housing. 
4 Check throttle position sensor  function by disconnecting  har- 
ness  connector  and checking across  terminals. If any faults 
are  found,  replace  throttle position  sensor. 
Engine coolant temperature (ECT)  sensor, 
testing and replacing 
Throttle  position  sensor (M62 engine) 
The  ECT  sensor is located  on the front  of the  engine  in the 
coolanVthermostat flange.The ECTsensor is a dual tempera- 
ture  sensor.  One circuit provides coolant  temperature infor- 
mation  to the ECM  while the other circuit provides  coolant 
temperature information  to the instrument  cluster. 
The ECM  determines  the correct ignition timing  and 
airlfuel 
mixture required  for the engine by monitoring  an applied  volt- 
age 
(5 vdc)  to the  sensor.  The voltage drop across the  sensor 
Test 
value 
5 vdc (approx.) 
4.0 kR(approx.) 
Continuously variable 
from 
1.0 to 4.0 kR 
without  interruption 
Test 
conditions 
Harness connector 
disconnected,  ignition  on 
Harness connector 
disconnected, 
ignition  on 
Throttle  plate  rotated  from idle to 
full throttle position  Test Terminal 
Term. 
1 at 
harness 
connector  and ground 
Term. 
1 and  term. 3 at 
sensor 
Term. 
1 and  term. 2 at 
sensor   
						

							
I Fuel lniection 
varies as the coolant temperature (sensor resistance) chang- 
es. 
NOTE- 
The  ECT  sensor  is an NTC (negative  temperature coeff- 
cient)  type sensor.  In other  words,  as the temperature rises, 
resistance through the sensor  decreases. 
If the ETC  sensor input is faulty  or non-plausible, the MILis il- 
luminated  when OBD 
II fault criteria  are exceeded.  The ECM 
assumes  a substitute  value 
(8OoC/176F) to maintain engine 
operation. The ignition timing is  set to a 
conservativelsafe ba- 
sic setting. 
4 Disconnect  ECT sensor harness  (A) 
- Checlc ECT sensor resistance  using a multimeter at  sensor 
terminals 
3 and 4. Peel back  protective boot (B) to  ID termi- 
nal  numbers  on connector housing. 
/ ECT sensor resistance @l 2O C (68°F) 2.2 - 2.7 kd 
WARNING - 
Due to risk of personal injug be  sure  the engine  is cold  be- 
fore  disconnecting  ECT harness  connector. 
Sensor replacement: Disconnect ECT  sensor harness  (A). 
- Unscrew  ECT sensor  from cylinder head  and install  new sen- 
sor. 
Use  new  copper sealing  washers 
when installing sensor. 
Replace  any lost coolant. 
Tightening torque 
ECT sensor  to coolant flange 13 Nm (I0 it-lb)   
						

							
Fuel Injection 
Intake air temperature 
([AT) sensor, 
testing and replacing 
Disconnect harness connector from  intake air temperature 
sensor 
(A) at  air filter housing. 
Turn  ignition  on. Using a digital voltmeter, check  for 
5 volts 
between  supply voltage wire  in connector  and ground. 
If volt- 
age is not present, test ECM 
inputs/outputs as described lat- 
er. 
With harness connector disconnected, test resistance across 
sensor terminals.  If any faults  are found, replace  IAT sensor. 
IAT test  resistance 
0 lV *lac (50  i-2°F) 7-1 1.6 k.0. 
020 kl°C (68 322°F) 2.1-2.9 it.0. 
080 ?lac (176 i-2°F) 0.27-0.40 itn 
Auxiliary throttle  valve (ADS) 
(M62 and M62  TU engine), replacing 
ADS components 540i  models with ASC  and DSC are fitted with a motor-driv- 
en auxiliary throttle  valve and housing  ahead of the standard Throttle  position  switch throttle housing. The ADS throttle valve controls engine throt- 
tle intervention  based on signals from the  DME control mod- 
ule  if road  conditions,  such as slipping  driven wheel, warrant 
reduced engine  power. 
ADS throttle housing 
Bowden cable NOTE- 
Before replacing the ADS throttle housing, read DME fault 
ADS lhroltle actualor codes. 
- ADS throttle  housing replacement: 
Switch  off ignition  and disconnect electrical connector  on 
ADS throttle  body. 
Remove hose from  idle control  valve. 
Loosen hose clamps  and remove throttle  housing  air in- 
take boot. 
Disconnect cable from ADS throttle  body. 
- Unscrew 3 bolts and remove ADS throttle  body. 
Installation is reverse  of removal. 
- Adjust cable so that  no free play is present.   
						

							
Fuel Injection Evaporative fuel system pressure leak 
diagnosis, overview 
(M5.2.1 only) 
1998 540i models are  equipped with  an evaporative  fuel sys- 
tem  pressure leak diagnosis system.  The main  component  of 
this system is  the leak diagnosis  pump (LDP).  The function  of 
the  LDP  is to  pressurize  the fuel  tank and  the evaporative 
emission system  for the purpose  of detecting 
leaks. This  sys- 
tem  is capable  of detecting  a leak as small as 0.5 mm. 
The  LDP,  located in  the left rear wheel housing,  is a unitized 
component that contains  the following: 
Vacuum chamber.  Pneumatic pump chamber. 
DME  activated vacuum  solenoid 
Reed switch (provides switched voltage 
feedback signal to 
ECM). 
The  vacuum supply  line is in  the wiring harness from  the en- 
gine compartment  and runs  down the  drivers side  of the vehi- 
cle. 
The  canister  vent valve  is integrated into  the LDP, which is 
electrically  controlled by the  ECM.  The canister vent valve is 
opened  to provide  fresh air entry into the  fuel system only dur- 
ing  purge operation. 
- Purge operation characteristics: 
Off idle through full throttle:  purge valve opened by  pulse 
width modulated (PWM)  control of the  ECM. PWM duty  cy- 
cle  varies by engine operating conditions 
(e.g. warm idle, 
purge valve  opened slightly; cold 
idleldecel with  engine 
temp 
< 67 C,  purge valve always closed).   
						

							
130-59 
Fuel Injection 
:-- -i. Evaporative emissions 
1. 
control diagram  (M5.2.1) 
i 1 
i I @ 1. ECM r.=.:-:, 2. Purge valve 
3. Leak detection pump  (LDP) 
4. Liquid vapor separator 
5. Purge canister 
6. Filter 
Bosch M5.2 ECM pin assignments 
(M62 up to 911997) 
Tabled. Bosch M5.2 ECM pin assignments 
I 1- 1. . . - 
4 1 output / Cyl. 4 fuel  injection  valve I Cyl. 4 fuel injection valve (cycled ground) 
Pin 
1 
2 
3 
i I 
I 
7 / output I Cyl. 6 fuel injection valve I Cyl. 6 fuel injection valve (cycled ground) 
Type 
output 
output 
output 
I  I , 
8 1 output I Malfunction indicator light (MIL) (USA only) I lliumlnated for exhaust gas related diagnostic trouble code 
5 
Component/function 
Oxygen sensor heater signal 
Idle speed control  -closing winding 
Cvl. 1 fuel iniection  valve  Note 
DME heated oxygen sensor 
1 splice 
idle speed control  valve (cycled ground) 
Cvl. 1 fuel iniection valve lcvcled around) 
6 1 ground I Fuel injection  valve ground 1 Ground 
output 
9 
Not 
used 
Not  used 
11 
12 
13 
Cyl. 5 fuel injection  valve 
10 1 input I Electronic immobilizer (EWS) / Electronic immobilizer (EWS) control unit 
input 
Heated oxygen sensor signal  Cyl. 
5 fuel injection 
valve (cycled ground) 
output 
input 
input 
16 
Start signal  Starter relay 
NC compressor signal 
Terminal 
50 signal 
Knock  sensor signal 
17 1 ground I Hot film  mass air flow (MAF) sensor ground I Hot film mass air flow (MAF) sensor ground 
output  Heating and 
A/C control module 
Ignition switch 
Knock  sensor 
Intake air temperature  intake air temperature sensor (voltage value)   
						

							
130-60 
/Fuel lniection 
Tabled. Bosch M5.2 ECM pin assignments 
Note 
Pin 
21 
20 I output / Crankshaft position sensor (speed and position) I Crankshaft positionlrpm sensor 
23 
I - I I 29 1 output I Idle speed control - opening winding I Idle speed control valve (cycled ground) 
Type 
22 
1 output I Cvl. 6  ignition signal  (primary signal) I Cyl. 6 ignition coil (RZV adapter) 
output 
25 
26 
27 
28 
Component/function 
24 1 outout I Cvl. 7  iqnition siqnal (primary signal) I Cyl. 7  ignition  coil (RZV adapter) 
output 
4 outbut I I - I Cyl. 3 
fuel injection valve I Cyl. 3 fuel injection valve (cycled ground) 
Camshaft position 
sensor (cylinder reference) 
output  input 
output 
oround 
30 
31 
32 
ground  Hall effect camshaft position sensor 
Cyl. 3  ignition signal (primary signal) 
output 
I 
Cyl. 3 ignition  coil (RZV adapter) 
. - . .. . . 
Cyl. 2  ignition signal (primary signal) 
Terminal  30 
Engine control module relay 
Ground  for electronics and sensor shield 
output 
output 
outout 
Remaining output stages  ground 
(not iclnition and fuel iniection valves)  Cyl. 
2 ignition  coil (RZV adapter) 
Fuse carrier, engine electronics 
Engine control module relay 
Ground splice , 
Cyl.  2 fuel injection valve 
Oxygen sensor heater signal 
Cyl. 5 
fuel injection valve 
Cvl. 8 fuel iniection valve 
AIC comuressor relav sianal 
Heated oxygen sensor I in  front  of catalytic converter, 
Heated oxygen sensor 
iI in  front of catalytic converter 
Cyl. 
5 fuel injection valve (cycled ground) 
Cvl. 8  fuel  iniection valve (cycled ground) 
. - 
Not used  Ground point 
Cyl. 
2 fuel injection valve (cycled ground) 
Heatinq and AIC control module (ground - compressor OFF) 
38  Not used 
40  39 
1 I Not used 
I 
I . I 
I I -. I 
46 1 ground I Heated oxygen sensor signal (voltage 0.1-1.0 V) I Oxygen sensors 
41 
1 inuut I Knock 
sensor signal I Knock  sensor 
input 
I 
I I 
Instrument cluster 
I I I 55 1 ground I Ignition ground I Ground point 
Knock sensor signal 
43 
1 I Not  used I 
Fuel reserve signal 
42 
Throttle position sensor 
47 
48 
49 
50 
51 
52 
53 
54 
Knoclc sensor 
input 
45 
1 outout I Hot  film  mass  air flow  sensor signal (0-5 V) I Hot film mass air flow sensor 
Throttle position sensor signal 
(0.4-4.2 V) 44 
input 
output 
output 
output 
output 
output 
inout 
I - I 
Not  used 
Not  used 
Cyl.  1 ignition signal (primary signal) 
Cyl. 5  ignition signal (primary signal) 
Cyl. 4  ignition signal (primary signal) 
Cyl. 8  ignition signal (primary signal) 
Throttle  position sensor 
(c 5 V  voltage supply) 
Terminal  87 
f> 10 V) 
ignition switch 
56 
Cyl. 1  ignition coil (RZV adapter) 
Cyi.  5 ignition coil (RZV adapter) 
Cyi. 
4ignition coil (RZV adapter) 
Cyl.  8 ignition coil (RZV adapter) 
Throttle position sensor 
Fuse 
F1 
input  Terminal 15 (> 10 V)