ect HONDA CIVIC 2003 7.G Workshop Manual

Fuel Pump/Fuel Gauge Sending Unit Replacement
SpecialTools Required
Fuel sender wrench 07XAA-001010A
1.Relieve the fuel pressure (see page 11-144).
Remove the fuel fill cap.
Remove the seat cushion (see page 20-80).
Remove the access panel (A)from the floor.
5.
7.
Disconnect the fuel pump 5P connector (B).
Disconnect the quick-connect fitting {C) from the
fuel tank unit.
Using the special tool, loosen the fuel tank unit
locknut (A).
93 N.m19.5 kgf.m,69 lbf.ftl
11-153
8. Remove the locknut (A) andthefuel tankunit.
9. Remove the stopper {O). Release the hook (P) and
remove the fuel filter (B), the fuel gauge sending
unit (C). the case (D), the wire harness (E), and the
fuel pressure regulator (F).
10. When connecting the fuel tank unit, make sure the
connection is secure and the suction filter (G) is
firmly connected to the f uel pump (H).
11. Install the fuel tank unit in the reverse order of
removal with a new base gasket (l)and new o-rings
(J), then check these items:
. When connecting the wire harness, make sure
the connection is secure and the connector (K) is
firmly locked into the place.
. When installing the f uel gauge sending unit,
make sure the connection is secure and the
connector is firmly locked into place. Be careful
not to bend or twist the connector excessively.. When installing the fueltank unit, align the marks
(L) on the fuel tank (M) and the fuel tank unit (Ni

Fuel Tank Replacement
Relievethefuel pressure (see page 11-144).
Drain the fuel tank: Remove the fuel pump (see page 1 1-153). Using a hand pump, hose, and container suitable for
gasoline. draw the fuel from the fuel tank.
Jack up the vehicle, and suppon it with safety stands.
Remove the fuel pipe cover (A). Disconnect the fuel vapor hose and quick-connect fittings.
Disconnect the hoses. Slide back the clamps (B), then twist the hoses as you pull to avoid damaging them.
A 38 N.m(3.9 ksf.m,28lbfft)
5. Place a jack or other support under the tank.
6. Removethe strap bolts, and letthestrap (C) hangfree.
7. Remove the fuel tank (D). lf itstickstothe undercoaton its mount, carefully pry itoffthe mount
8. Install the parts in the reverse order of removal.
1.
2.
3.
(}
\
11-155

Fuel Supply System
Fuel Gauge Sending Unit Test
Special Tools Required
Fuel sender wrench 07XAA-001010A
NOTE; For the fuel gauge system circuit diagram, referto the Gauges Circuit Diagram (see page 22-58||.
1. Checkthe No. 10 fUETER {7.5A)fuse in the under-
dash fuse/relay box before testing.
2. Do the gauge drive circuit check (see page 22-56|l.
' lf the fuel gauge needle sweeps from minimuni
to maximum position and then returns to the
minimum position. the gauge is OK. Go to step 3.. lf the fuel gau ge need le does not sweep from
minimum to maximum position position and
then return to the minimum position, replace thegauge assembly and retest.
3. Turn the ignition switch OFF.
4. Remove the rear seat cushion {see page 20-80).
5. Remove the access panel (A)from the floor.
6. Disconnect the fuel pump 5P connector {B).
-ztr
11-156
7. Measure voltage between fuel pump 5P connectorterminals No. 1 and No. 2 with the ignition switchON (ll). There should be battery voltage.
. lf the voltage is as specified, go to step 8.. lf the voltage is notasspecified,checkfor:
- an open in the YEUBLK or BLK wire.- poor ground (G551).
FUEL PUMP 5P CONNECTOR
Wire side of female terminals
Turn the ignition switch OFF. Remove the No. 9BACK UP (7.5A)fuse from the under-hood fuse/
relay box for at least 10 seconds, lhen reinstall it.
Install a 2 Q resistor between fuel pump 5P
connector lerminals No. 1 and No. 2, then turn the
ignition switch ON (ll).
FUEL PUMP 5P CONNECTOR
-VVV-
29RESISTOR,
=-a
{Y
\
//,(elrt \
\45/
{YEL/BLK)
Wire side of female terminals

10. Checkthatthe pointerof thefuel gauge indicates"F".
. lf the pointer does not indicate "F", replace the
ga uge.. lf the pointer indicates "F", inspect the fuel
gauge sending unit.
NOTE: The pointer of the fuel gauge retu rns to the
bottom of the gauge dial when the ignition switch
is OFF, regardless of the fuel level. -
11. Relieve the fuel pressure (see page 11-144\.
12. Remove the fuelfill cap.
13. Disconnect the quick-connect fittings from the fuel
pump.
14. Using the special tool, loosen the fuel tank unit
locknut (A).
A93Nm{9.5 ksf.m,69 lbf.ft}
15. Measure resistance between the No. 1 and No.2
terminals with the float at E (EN4PTY), 'l12 \HALF
FULL), and F {FULL) positions.
lf you do not get the following readings, replace the
fuel gauge sending unit {see page 1'1-163).
Float
Position
F'U2LOWE
Resistance
{0)
11
to 13
68,5
to 74.5
114.4
to 126.6
130
to 132
NOTE: Remove the No. 9 BACK UP (7.5A) fuse from
the under-hood fuse/relay box for at least 10
seconds after completing troubleshooting,
otherwise it may take up to 20 minutes for the fuel
gauge to indicate the correct fuel level.
11-157

Intake Air System
Throttle Body Test
NOTE:. Do not adjust the throttle stop screw. lt is preset at the
factory.. lf the malfunction indicator lamp (MlL) has been
reported on, check for diagnostic trouble codes(DLCS) (see page 11 3).
1. With the engine off, check the throttle cable
movement. The cable should move without binding
or sticking.
. lf lhe cable moves OK, goto step 2.. lf the cable binds or sticks, check it and its routing.. lf the cable isfaulty, reroute itor replace itand
adjust it (see page 11-163), then go to step 2.
2. l\4ove the throttle lever by hand to see if the throftle
valve and/or shaft are too loose or too tight.
. lf there is excessive play in the throttle valve
shaft, or any binding in the throttle valve at the
fully closed position, replace the throttle body.. lf thethrottlevalve and shaft are OK, goto step3.
3. Connect the scan toolto the DLC.
Turn the ignition switch ON (ll).
Check the throttle position with the scan tool. The
reading should be about 10% when the throttle is
fully closed and about 90% when the throttle is fully
openeo.
. lf the throttle position is correct, the throttle body
is OK.. lf thethrottle position is notcorrect, replace the
throttle body.
5.
11-160
!

Intake Air Bypass GontrolThermalValve Test
Special Tools Required
Vacuum Pump/Gauge,0 30 in. Hg A973X-041-XXXXX
1. Stan the engine. Then let it idl€.
NOTE: The engine coolant temperature must be
below 149'F (65'C).
2. Remove the vacuum hose (A)from the intake air
duct, and connect a vacuum pump/gauge to the
nose.
3. Raise and lowerthe engine speed. and make sure
the vacuum gauge reading changes as the engine
speeo cnanges.
lf the vacuum reading does not change, check for
these problems:
. Misrouted, leaking, broken, or clogged intake air
bypass control system vacuum lines.. A cracked or damaged intake air bypass control
thermal valve.
4. Hold the engine at 3,000 rpm with no load (in
neutral) until the radiator fan comes on, then let it
id le.
5. Raise and lower the engine speed, and make sure
the vacuum gauge reading does not change as the
rpm cnanges.
lf the vacuum reading changes, check for these
proorems:
. l\4isrouted, leaking, broken, or clogged intake air
bypass control system vacuum lines.. A cracked or damaged intake air bypass control
thermal valve.
11-161

Intake Air System
1. Remove the nuts (A) and the stud (B).
Air Cleaner Replacement
Remove the air cleaner (C).
Install in the reverse order of removal.
2.
3.
11-162
Air Cleaner Element Replacement
1. Disconnect the PCV hose 1A).
Open the air cleaner housing cover (B).
Remove the air cleaner (C) from the air cleaner
housing (D).
Install in the reverse order of removal.
2.
3.\,
4.
{0.3 kgf m,2lbf.ft)

PCV Valve Inspection and Test
2.
1. Check the PCV valve (A), hoses {B), and
connections for leaks or restrictions.
At idle, make sure there is a clicking sound from the
PCV valve when the hose between the PCV valve
and intake manifold is lightly pinched {A)with your
fingers or pliers.
lf there is no clicking sound, check the PCV valve
grommet for cracks or damage. lf the grommet is
OK. reDlace the PCV valve and recheck.
PCV Valve Replacement
'LDisconnect the PCV hose.
Remove the PCV valve (A).
3. Install
with a
(4.5 kgf.m,33 lbf.ft)
the parts in the reverse order of removal
new gasket (B).
11-169

DTC Troubleshooting
DTC P0451: FTP Sensor Range/Performa nce
Problem
Special Tools Required
Vacuum Pump/Gauge, 0-30 in. Hg A973X-041-XXXXX
1. Remove the fuel fill cap.
2. Turn the ignition switch ON (ll)
3. l\4onitor fuel tank pressure (FTP) sensorvoltage
with the Honda PGM Tester, or medsure voltage
between ECM connectorterminals E4 and E14.
ECM CONNECTOR E 131P)
Wire side of female terminals
ls there about 2.5V?
YES-Go to step 4.
NO Replace the FTP sensor.I
Turn the ignition switch OFF.
Disconnect the hose between the EVAP two way
valve and the FTP sensor at the EVAP two way
valve end.
4.
5.
7.
8.
6. Connect a vacuum pump to the open end of the
hose.
Turn the ignition switch ON {ll).
l\4onitor FTP sensor voltage with the Honds PGM
Tester, or measure voltage between ECM
connector terminals E4 and E14, and carefully
squeeze the vacuum pump a little.
ECM CONNECTOR E 13lPI
Wire side of lemale terminals
The voltage should smoothly drop from about 2.5 V
to about 1.5 V. Stop applying vacuum when the
voltage drops to about 1.5 V or damage to the FTP
sensor may occur.
Does the voltage drop to about 1.5 V and hold?
YES Check for misrouted, leaking, or broken FTP
sensor vacuum lines. lf the vacuum lines are OK,
update the ECM if it does not have the latest
software. or substitute a known-good ECM, then
recheck (see page 1 1-6). lf the symptom/indication
goes away with a known-good ECM, replace the
original ECM.I
NO Replace the FTP sensor. !
9.
11-171

EVAP System
DTC Troubleshooting (cont'd)
DTC P0452: FTP Sensor Circuit Low Voltage
1. Check the vacuum lines at the FTP sensor for
misrouting, leakage. breakage, or clogging.
Are the vacuum lines OK?
YES Go to step 2.
NO Repair or replace vacuum lines as
necessary. I
2. Reset the ECM (see page 11-4).
3. Remove the fuelfill cap.
4. Turn the ignition switch ON (ll)
5. Monitor FTP sensor voltage with the Honda PGM
Tester, or measure voltage between body ground
and ECM connector terminal E14.
ECM CONNECTOR E 131PI
1 2t3t45o/89
././114tc61./182C21
22123241 t26271/ 2931
TP (LT GRN)
Wire side of female terminals
ls thete about 2.5 V?
YES- Intermittent failure, system is OK at this time.
Check for poor connections or loose terminals at
the FTP sensor and at the ECrM.l
NO Go to step 6.
11-172
6. Turn the ignition switch OFF.
7. Reinstallthe fuel fill cap.
8. Disconnect the FTP sensor 3P connector.
9. Turn the ignition switch ON (ll)
10. Measure voltage between FTP sensor 3P connector
terminals No. 1 and No.2.
FUEL TANK PRESSURE SENSOR 3P CONNECTOR
VCgl {YEL/BLU}
Wire side of female terminals
ls there about 5 V?
YES Go to step 1 '1.
NO-Repair open in the wire between the FTP
sensor and the ECM {E5).1