lgnition System
5.
lgnition Timing Inspection and Setting
2.
1.Check the idle speed, and adjust it if necessary (see
section 1 1).
Pull out the service check connector 2P (BRN and
BLK wires) from the connector holder located under
the dash on the front passenger side, then connect
the scs service connector (P/N 07PAz - 0010100) to
it.
Start the engine. Hold the engine at 3,000 rpm with
no load (A/T in N or E, Mff in neutral) until the
radiator fan comes on, then let it idle.
Connect the timing light to the No. I ignition wire,
then point the light toward the pointer on the timing
belt cover.
Check the ignition timing in no load conditions:
headlights, blower fan, rear window defogger, and
air conditioner are not operating.
lgnition Timing:
M/T: 16" 12" BTDC (RED) idling in neutral
AlTt'16" !2" BTDC (RED) idling in E or E
CRANKSHAFTPULLEY
4-16
6. lf necessary, adjust the ignition timing as follows.
Loosen the distributor mounting bolts, and turn the
distributor ignition (Dl) housing counterclockwise to
advance the timing or clockwise to retard the tim-
t no,
7.
8.
MOUNTING BOLTS24 N.m {2.4 kgf m, 17 lbtft}
Tighten the distributor mounting bolts, and recheck
the ignition timing.
Disconnect the SCS service connector from the ser-
vice check connector.
To RETARD
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ECM/PCM Data
By connecting the OBD ll scan tool or the Honda PGM Tester to the 16P data link connector (OLC), various data can be
retrieved from the ECM/PCM. The items listed in the table below conform to the SAE recommended practice
The Honda PGM Tester also reads data beyond that recommended by SAE.
understanding this data will help to find the causes of intermittent failures or engine problems.
NOTE:
The ',operating values" given below are approximate values and may be different depending on the environment and
the individual vehicle.
Unless noted otherwise. "at idle speed" means idling with the engine completely warmed up, transmission in position
Park or neutral and the A,./C and all accessories turned otf.
DataDesc.iptionOp€rating ValuoFreeze Data
Diagnostic
Trouble Code
(DTC)
lf the ECM/PCM detects a problem, it will store it as a
code consisting of one letter and tour numbers
Depending on the problem, an SAE-defined code (Poxxx)
or a Honda-defined code (P'lxxx) will be output to the
tester.
lf no problem is detected,
there is no output.
YES
Engine SpeedThe ECN4/PCN4 computes engine speed from the signals
sent from the Crankshaft Position sensor.
This data is used for determining the time and amount of
fuel iniection.
Nearly the same as
tachometer indication
At idle speed:'97 - 98 models:
750 t 50 rpm'99 - 00 models:
730 f 50 rpm
YES
Vehicle SpeedThe ECM/PCM converts pulse signals from the Vehicle
Speed Sensor (VSSI into speed data.
Nearly the same as
speedometer indicationYES
Manifold
Absolute
Pressure (MAP)
The absolute pressure caused in the intake manifold by
engine load and speed.
With engin6 stopped:
Nearly the same as atmo-
spheric pressure
At idle speed:
2a - 41 kPa {210 - 310
mmHg, 8.3 - 12.2 inHg)
YES
Engine Coolant
Temperature
{ECT)
The ECT sensor converts coolant temperature into volt-
age and signals the ECM/PCM. The sensor is a thermistor
whose internal resistance changes with coolant tempera-
ture. The ECM/PCM uses the voltage signals from the
ECT sensor to determine the amount of injected fuel
With cold engine:
Same as ambient temPer-
ature and IAT
With engine warmed uP:
approx. 163 - 2'12'F
(73 - 100"c)
YES
Heated Oxygen
Sensor (HO25)
(Primary,
Sensor 1)
(Secondary
Sensor 2)
The Heated Oxygen Sensor detects the oxygen content in
the exhaust gas and sends voltage signals to the
ECMiPCM. Based on these signals, the ECM/PCM controls
the airlfuel ratio. When the oxygen content is high (that is.
when the ratio is leaner than the stoichiometric ratio), the
voltage signal is lower.
When the orygen content is low (that is, when the ratio
is richer than the stoichiometric ratio), the voltage signal
is higher.
0.0 - 1.25 V
At idle speed:
about 0.1 - 0.9
NO
(cont'd)
1 1-65
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Troubleshooting
Troubleshooting Procedures (cont'd)
DataDescliptionOperating ValueFreezo Data
HO2S
Feedback
Loop Status
Loop status is indicated as "open" or "closed".
Closed: Based on the HO2S output, the ECM/pCM deter-mines the airlfuel ratio and controls the amount ofinjected fuel.
Open: ignoring HO2S output, the ECM/pCiM refers to sig,nals from the TP, MAP, and ECT sensors to control theamount of injected fuel.
At idle speed: closed
YES
Short Term
Fuel Trim
The airlfuel ratio correction coefficient for correcting theamount of injected fuel when HO2S feedback is in theclosed loop status. When the signal from the HO2S isweak, short term fuel trim gets higher, and the ECM/PCMincreases the amount of injected fuel. The airlfuel ratiogradually gets richer, causing a higher HO2S output.Consequently. the short term fuel trim is lowered. andthe ECM/PCM reduces the amount of injected fuel.This cycle keeps the airfuel ratio close to the stoichio-metric ratio when in closed looD status.
t:20y"
YES
Long Term
Fuel Trim
Long term fuel trim is computed from shon term fueltrim and indicates changes occuring in the fuel supplysystem over a long period.
lf long term fuel trim is higher than 1,00. the amount ofinjected fuel must be increased. lf it is lower than L00.the amount of injected fuel must be reduced.
! 20%
Intake Air
Temperature
(IAT)
The IAT sensor converts intake air temperature into volt-age and signals the ECrU/PCM. When intake air tempera-ture is low, the internal resistance of the sensorincreases, and the voltage signal is higher.
With cold engine:
Same as ambient temper-
ature and ECTYES
Throttle
Position
Based on the accelerator pedal position, the openingangle of the throttle valve is indicateo.At idle speed:
approx. 10%
lgnition
Timing
lgnition timing is the ignition advance angle set by theECM/PCM. The ECM/PCM matches ignition timing to thedriving conditions.
At idle speed: 16'1 4.
BTDC with the SCS ser-
vtce connector connected.
NO
Calculated
Load Value(cLV)
CLV is the engine load calculated from the MAp data.At idle speed:
2A - 410/o
At 2,500 rpm with no load:
13 - 260/o
YES
_
1 1_66
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ldle Control System
Fast ldle Thermo Valve lA/T)
Description
To prevent erratic running when the engine is warming
up, it is necessary to raise the idle speed. The fast idle
thermo valve is controlled by a thermowax plunger.
When the engine is cold, the engine coolant surround-
ing the thermowax contracts the plunger, allowing addi-
tional air to be bvDassed into the intake manifold so that
the engine idles faster. When the engine reaches operat-
ing temperature. the valve closes, reducing the amount
of air bypassing into the intake manifold.
IDLEADJUSTING
IDLETHERMOVALVE
AIR BYPASS VALVE
11-168
Inspgction
NOTE: The fast idle thermo valve is factory adjusted; it
should not be disassembled.
1. Remove the intake air duct from the throttle body.
2. Start the engine,
3. Put your finger over the lower port in throttle body,
and make sure that there is air flow with the engine
cold (engine coolant temperature below 86"F, 30'C).
lf there is no air flow, replace the fast idle thermo
valve and retest,
O-RINGSReplace.
11.0 kgfl.m, 7.2 lbl.ftl
Start the engine. Hold the engine at 3,000 rpm with no
load (in Park or neutral) until the radiator fan comes
on, then let it idle.
Check that the valve is completely closed. lf the valve
is leaking, the idle speed will drop when you cover the
lower pon. Check the engine coolant level and for air
in the engine cooling system {see section 10). lf the
cooling system is OK, replace the fast idle thermo
valve and recheck.
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25. Remove the transmission mounting bolts and the
rear engine mounting bolts.
REAR ENGINE MOUNTING BOLTSReplace.
TRANSMISSION
Pull the transmission away from the engine until it
clears the mainshaft, then lower it on the transmis-
sion jack.
NOTE: Take care not to bend the clutch line.
Remove the starter motor and hose clamp from the
transmission housing.
STARTERMOTOR
28. Remove the release tork boot. release bearing, and
release fork from the clutch housing
RELEASEBEANING
13-1 1
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Description
General Operation (cont'dl
Gsar Selection'97 - 98 Models
The shift lever has seven positions; El PARK, ts REVERSE, N NEUTRAL, Ell 1st through 4th ranges, lpq 1st th.ough 3rdranges, P 2nd gear, and [ 1st gear
'99 - 00 Models
The shitt lever has six positions; El PARK, E REVERSE, E NEUTRAL. E ,lst through 4th ranges, and 1st through 3rd(when Over-Drive (O/D) is OFF) ranges. @ 2nd gear, and E 1st gear.
Starting is possible only in @ and @ positions. using a slide-type. neutral-safety switch.
Automatic Transaxle (A/T) Gear Position IndicatorThis indicator in the instrument panel shows which gear has been selected.
Transler Mochanism {4WD}
The transfer mechanism consists of the transfer shaft drive gear. the transfer shaft. the transfer drive gear, the transfer driv-en gear shaft, and the companion flange, The transfer mechanism assembly is on the rear side ot the transmission. besidethe differential. The transfer shaft drive gear on the final driven gear drives the transfer shaft driven qear. power is transmit-ted to the rear differential via the transfer shaft and the Drooeller shaft.
Clutches
The four-speed automatic transmission uses hydraulically-actuated clutches to engage or disengage the transmission gears.When the hydraulic pressure is introduced into the clutch drum, the clutch piston moves. This presses the friction discs andsteel plates together, locking them so they don't slip. Power is then transmifted through the engaged clutch pack to its hu$mounted gear. When hydraulic pressure is bled from the clutch pack, the piston releases the friction discs and steel plates, andthey are free to slide past each other. This allows the gearto spin independently on its shaft, transmitting no power.
lst Clutch
The 1st clutch engages/disengages lst gear, and is located at the end ofthe mainshaft, just behind the end cover.The 1st clutch is supplied hydraulic pressure by its ATF feed pipe within the mainshaft.
lst-hold Clutch
The 1st-hold clutch engages/disengages 1st-hold or E position, and is located at the middle of the sub-shaft. The 1st-holdclutch is supplied hydraulic pressure by its ATF feed pipe within the sub-shaft.
2nd Clutch
The znd ciutch engages/disengages 2nd gear, and is located at the middle of the mainshaft. The 2nd clutch is joined back-to-back to the 4th clutch. The 2nd clutch is supplied hydraulic pressure through the mainshaft by a circuit connected to theinternal hydraulic circuit.
PositionDescription
Reverse; reverse selector engaged with countershaft reverse gear and 4th clutch locked.
Allclutches released.
General driving; starts off in 1st, shifts automatically to 2nd, 3rd, then 4th, depending on vehicle speedand throftle position. Downshifts through 3rd,2nd, and lst on deceleration to stop.The lock-up mechanism operates;n 3rd and 4th gear.
used for rapid €cceleration at highway speeds and general driving; stans off in 1st, shifts automatically to2nd_then 3rd, dejending on vehicle speed and throttle position. Downshifts through lower gears on decel-eration to stop. The lock-up mechanism comes into operation in 3rd gear.
Driving in 2nd_gear; stays in 2nd gear, does not shift up and down. For engine braking or better trac_tion starting off on loose or slippery surfaces.
Driving in 1st gear; stays in 1st gear, does not shift up. For engine braking.
tll PARK
t!!l l|EvEn>E
E NEUTRAL
Ell DRrvE ('97 - sB)E DRrvE ('ss - oo)(1st through 4th )
E DRrvE {'97 - s8)O DRTVE with over-Drive (O/D) is OFF('99 - 00)(1st through 3rd)
E SECOND
E FIRST
14-4
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28. Place a jack under the transmission, raise it just
enough to take it off of the mounts, then remove
the transmission mount bracket.
Remove the front side transmission housino mount-
ing bolt.
29.
30. R€move the rear side transmission housing mount-
ing bolt and the rear engine mounting bolts.
Pull the transmission away from the engine until it
clears the dowel pins, then lower it on the transmis-
sion jack.
Remove thg torque converter assembly from the
transmission.
Remove the starter from the transmission housing.
31.
REAR ENGINE MOUNTING BOLTS
14-173
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REAR MOUNT
20. Remove the rear mount bracket and rear mount.
12 x 1.25 mmReplace.
REAR MOUNT BRACKET12 x 1.25 mmReplace.
21.
14 x 1.5 mmReplaco.
Place a jack under the engine block in the area
shown,
?*
JACK.UP POINT
17-33
22. Jack up the engine and tilt the engine back until the
transfer assembly is lowered approximately 40 mm
(1.57 in).
Note these items when tilting the engine:
. Check that the wire harnesses, hoses and pipes
are not caught by any surrounding parts.
. Do not tilt the engine more than necessary.
ASSEMBLY
Remove the stiffener olate.
NOTE: Some stiffener plate mounting bolts a.e also
used as gearbox mounting bolts. The gearbox will
tilt to the side when these bolts are removed.
(cont'd)
.Lower approximately'40 mm (1.57 in)
STIFFENER PLATE
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