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....

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...

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...

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...

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...

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...

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...

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...

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...

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...