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...

.. .- 
/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...

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,...

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...

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...

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...

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....

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...

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...

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...