fuel pressure sensor HONDA CIVIC 2002 7.G User Guide

Fuel and Emissions Systems
System Descriptions (cont'd)
PGM-FI System
The Programmed Fuel Injection (PGM-Fl) system is a
sequential multiport fuel injection system.
Air Conditioning {A/C) Compressor Glutch Relay
When the ECfM receives a demand for cooling from the
Ay'C system, it delays the compressor from being
energized, and enriches the mixture to assure smooth
transition to the AVC mode.
Air Fuel Ratio lA/Fl Sensor
The Ay'F Sensor operates over a wide airlfuel range. The
Ay'F Sensor is installed upstream of the TWC, and sends
signals to the ECM which varies the duration of fuel
injection accordingly.
SENSORTERMINALS
HEATERTERMINALS
Barometric Pressure {BAROI Sensor
The BARO sensor is inside the ECM. lt convens
atmospheric pressure into a voltage signal that the ECM
uses to modify the basic duration of the fuel injection
discharge.
ztRcoNtaELEMENT
HEATER
11-26
\,
Camshaft Position (CMPI Sensor B (Top Dead Center(TDCI Sensor)
The CMP sensor B (TDC sensor) detects the position of
the No. 1 cylinder as a reference for sequential fuel
injection to each cylinder.
Crankshaft Position (CKPI Sensor
The CKP sensor detects crankshaft soeed and
determines ignition timing and timing for fuel injection
of each cylinder as well as detecting engine misfire.
Engine Coolant Temperature (ECT) Sensor
The ECT sensor is a temperature dependent resistor(thermistor). The resistance of the thermistor decreases
as the engine coolant temperature increases.
MAGNET
TERMINAL

lgnition Timing Control
The ECM contains the memory for basic ignition timing
at various engine speeds and manifold absolute
pressure. lt also adjusts the timing according to engine
coolant temperature.
Iniector Timing and Duration
The ECM contains the memory for basic discharge
duration at various engine speeds and manifold
pressures. The basic discharge duration, after being
read out from the memory, is further modified by
signals sent from various sensors to obtain the final
discharge duration.
By monitoring long term fuel trim, the ECM detects long
term malfunctions in the fuel system and sets a
Diagnostic Trouble Code {DTC).
Intake Air Temperature (lAT) Sensor
The IAT sensor is a temperature dependent resistor
{thermistor). The resistance of the thermistor decreases
as the intake air temDerature increases.
Knock Sensor
The knock control system adjusts the ignition timing to
minimize knock.
PIEZOCERAMIC
Malfunction Indicator Lamp lMlLl Indication {ln relation
to Readiness Codes)
The vehicle has certain "readiness codes" that are part
of the on-board diagnostics for the emissions systems.
lf the vehicle's baftery has been disconnected or gone
dead. if the DTCS have been cleared, or if the ECM has
been reset. these codes are set to incomplete. In some
states, part of the emissions testing is to make sure
these codes are set to comDlete. lf all of them are not
set to complete, the vehicle may fail the test and the
test cannot be finished.
To check if the readiness codes are set to complete,
turn the ignition switch ON (ll). but do not start the
engine.TheMILwill comeonforlS 20seconds. lf it
then goes off, the readiness codes are set to complete,
lf it blinks severaltimes, one or more readiness codes
are not set to comolete. To set each code, drive the
vehicle or run the engine as described in the
procedures to set them in this section (see page 1 1-46).
Manifold Absolute Pressure {MAP) Senso]
The MAP sensor converts manifold absolute pressure
into electrical signals to the ECM.
SENSOR UNIT
(cont'd)
11-27

Evaporative Emission (EVAPI Control
System
Refer to the System Diagram to see the functional
layout of the system.
EVAP Canister
The EVAP canister temporarily stores fuel vapor from
the fuel tank until it can be purged back into the engine
and burned.
EVAP Canister Purge Valve
When the engine coolant temperatu re is below 149'F(65'C), the ECM turns off the EVAP canister purge valve
which cuts vacuum to the EVAP canister.
FuelTank Pressure (FTP) Sensor
The FTP sensor converts fueltank absolute pressure
into an electrical inputto the ECM during the EVAP leak
cnecK.
SENSOR UNIT
EVAP Two Way Valve and EVAP Eyp8s Solenoid
Valve
The EVAP two way valve is installed between the fuel
tank and the EVAP canister line.
The EVAP two way valve sends fuel vapor to the EVAP
canister corresponding to the pressure inside the tuel
tank. lt also relieves excess vacuum in the tank by
allowing fresh air to be drawn into the tank through the
EVAP canister.
The EVAP bypass solenoid valve opens to bypass the
two way valve during the EVAP leak check.
EVAP BYPASSSOLENOID VALVE
VALVE
(cont'd)
To FUEL TANK
11-35

PGM-FI System
Component Location Index
CAMSHAFT POS]TION {CMP) SENSOR B(TOP DEAD CENTER (TDC}SENSORITroubleshootina. oaoe 1 1-95Replacement, p;ge 1-1.1 14
ELECTRICAL LOADDETECTOR {ELDITroubleshooting,page 1'l -92
INTAKE AIR TEMPERATURE{IATI SENSORTroubleshooting,page 'l'l-55
Replacement, page 11-'l 15
f- \
rl
KNOCK SENSORTroubleshooting, page 1 1-77Beplacement, page 11 115
ENGINE COOLANT TEMPERATURE(ECTI SENSORTroubleshooting, page 1 1-57Replacement, page 11 114
MANIFOLD ABSOLUTE PRESSURE(MAP) SENSORTroubleshooting, page 1 1-52
THROTTLE POSITIONITP} SENSORTroubleshooting, page 11-60CRANKSHAFT POSITIONICKPISENSORTroubleshooting, page'l 1-78Beplacement, page 1 1-'l 16
AIR FUEL RATIO {A/F)SENSOR ISENSOR 1}Trorrbleshooting, page 1 1-84Replacement, page 11- 1 13
{cont'd)
ii'- r'1
.I11 ---:,I''.!,i(..,.?:fir-J-
.....,..:--.
11-49

PGM-FI System
DTC Troubleshooting (cont'dl
DTC P0171: Fuel System Too Lean
DTC P0172: Fuel System Too Rich
NOTE: lf some of the DTCS listed below are stored at
the same time as DfC PO17'l and/ot PO172,
troubleshoot those DTCS first, then recheck for P0171
andlot P0112.
P0107, P0108. P1 128. P1 129: Manifold absolute
pressure (MAP) sensor
P1 162. P1 166, P 1 167: 4,,/F sensor (Sensor 1 ) heater
P0137, P0138: Secondary HO2S (Sensor 2)
P014'l: Secondary HO2S (Sensor 2) heater
P1259: VTEC system
1. Check the fuel pressure (see page 11-'145).
ls luel pressure OK?
YES Go to step 2.
NO Check these items:
. lf the pressure is too high, replace the fuel
pressure regulator (see page 11-152).1. lf the pressure istoo low.checkthefuel pump,
the fuel feed pipe, the fuel filter, and replace the
fuel pressure regulator (see page 11-152).I
2. Start the engine. Hold the engine at 3,000 rpm with
no load (in neutral) until the radiator fan comes on.
11-70
3. Turn the ignition switch OFF.
4. With a vacuum pump, apply vacuum to the
evaporative emission (EVAP) canister purge valve
(A) from the evaporative emission (EVAP) canister
side.
' A973AX-041-XXXXX
Does it hold vacuum?
YES-Check the engine valve clearances and adjust
if necessary, lf the valve clearances are OK, replace
the injectors (see page 1 1-1 1 1).1
NO-Replace the EVAP canister purge valve.l

DTC P0300: Random Misfire and Any Combination of the Following:
DTC P0301: No. 1 Cylinder Misfire
DTC P0302: No. 2 Cvlinder Misfire
DTC P0303: No, 3 Cvlinder Misfire
DTC P0304: No. 4 Cvlinder Misfire
NOTE:. lfthe misfiring is frequent enough to trigger detection of increased emissions during two consecutive driving cycles.
the MIL will come on, and DTC P0300 (and some comlrination of P0301 through P0304) will be stored.. lf the misfiring is frequent enough to damage the catalyst, the MIL will blink whenever the misfiring occurs, and OTC
P0300 (and some combination of P0301 through P0304) will be stored. When the misfirlng stops, the MIL will remain
on.
1. Troubleshoot the following DTCs first if any of them were stored along with the random misfire DTC(s):
P0'107, P0108, P1128, P1129r N4anifold absolute pressure (MAP) sensor
P0111. P0'172t Fuel svstem
P0335. P0336: Crankshaft position (CKP) sensor
P0505: ldle control system
P1 149, Pl 162, P1 163, P1 164, P 1 165: Air fuel ratio (Ay'F) sensor
P1259: VTEC system
P1361, P1362: Camshaft position (CMP) sensor B {Top dead center (TDC) sensor)
P1519: ldle air control (lAC) valve
2. Test-drive the vehicle to verify the symptom.
3. Findthesymptom inthechart below, and dothe related procedures in the order listed until you find the cause.
SymptomProcedure(slAlso check foi:
Random misfire only
at low RPM and
under load
Check fuel pressure (see page 1 1-145).. Low compressron.. Low quality fuel.
Random misfire only
du ring acceleration
Check fuel pressure (see page 11-145).Malfunction in the
VTEC system (see page
1't-123).
Random misfire at
high RPM, under
load, or under
random conditions
Check fuel pressure (see page 11-145).Correct engine valve
clearances (see page 6-
91.
11-71

MIL Circuit Troubleshooting
1. Connect an OBD ll scan tool/Honda PGM Tester
(see page 11-3).
2. Turn the ignition switch ON (ll) and read the OBD ll
scan tool/Honda PGM Tester.
Does the OBD ll scan tool/Honda PGM Tester
communicate with the ECM?
YES Go to step 3.
NO Go to troubleshooting " DLC Circuit
Troubleshooting" (see page 11-109).
3. Check the OBD ll scan tool/Honda PGM Testerfor
DTCs.
Are any DTCs ind icated?
YES Go to the DTC Troubleshooting Index.
NO-Go to step 4.
4. Turn the ignition switch OFF.
5. Turn the ignition switch ON (ll)and watch the
lMalfunction Indicator Lamp (MlL).
Does the MIL come on and stay on for more than
20 seconds aftet turning the ignition switch
oN (tr)?
YES lf the MIL always comes on and stays on, go
to step 76. But if the lMlL sometimes works
normally, first check for these problems.
. An intermittent short in the wire between the
ECIM (E29) and the data link connector (DLC).
. An intermittent short in the wire between the
ECM (E31) and the gauge assembly.
NO lf the MIL is always off, go to step 6. But if the
lvllL sometimes works normally, first check for
these problems.
. A loose No. 10 METER (7.5A) fuse in the under
dash fuse/relay box.. A loose No. 20 lG (40A) (Canada: 50A)Iuse in the
under-hood fuse/relay box.. A ioose No. 6 ECU (ECM) (15A) fuse in the under-
hood fuse/relay box.
. A loose No. 17 FUEL PUMP (15A)fuse in the
under-dash fuse/relay box.. A poor connection at ECM terminal E31.. An intermittent open in the GRN/ORN wire
between the ECM (E31) and the gauge assembly.. An intermittent short in the wire between the
ECM (A21) and the manifold absolute pressure
(MAP) sensor.. An intermittent short in the wire between the
ECI\4 (A20) and the throttle posilion (TPi sensor.. An intermittent short in the wire between the
ECM (E5) and the fuel tank pressure (FTP) sensor.
6. Turn the ignition switch OFF.
7. Turn the ignition switch ON (ll).
ls the low oil pressure light on?
YES Go to step 10.
NO-Go to step 8.
8. Inspectthe No. 10 l\4ETER (7.5A)fuse inthe under-
dash fuse/relay box.
ls the luse OK?
YES Go to step L
NO Repair shon in the wire between No. 10
METER (7.5A)fuse and the gauge assembly. Also
replacethe No. 10 METER {7.5A) fuse.l
9. Inspect the No. 20 lG1 (40A) (Canada: 50A) fuse in
the under-hood fuse/relay box.
ls the f use OK?
YES Repair open in the wire between the No. 20
lG (40A) {Canadar 50A)fuse and the gauge
assembly. lf the wire is OK, test the ignition switch
{see page 22 53).
NO Repair short in the wire between No. 20 lG
(40A) lCanada: 50A)fuse and the under'dash fusel
relay box. Also replace the No.20 lG (40Ai
(Canada: 50A) fuse.I
(conr'd)
11-97

PGM-FI System
67.
MIL Circuit Troubleshooting (cont'd)
Check for continuity between ECIM connector
terminal A20 and body ground.
ECM CONNECTOR A (31P)
rl2l3145ot/9
10t1121,/ 1,/1516ta,92A21
22 '3241 12526n
o
Wire side of female terminals
ls there continuity?
YES Repair shon in the wire between the ECN4
{A20) and the TP sensor, or repair short in the wire
between the ECM (A8) and the knock sensor. t
NO Update the ECM if it does not have the latest
software. or substitute a known-good ECM, then
recheck (see page l1-6). lf the symptom/indication
goes away with a known-good ECM, replace the
original ECM.t
vcc2{YEL/BLU}
11-106
68. Measure voltage between body ground and ECM
connector terminal E5.
ECM CONNECTOR E (31PI
Is there about 5 V?
YES U pdate the ECM if it does not have the latest
software, or substitute a known-good ECM, then
recheck (see page 11-6). lf the symptom/indication
goes away with a known-good EClvl, replace the
original ECM.t
NO-Go to step 69.
Turn the ignition switch OFF.
Disconnect the fuel tank pressure (FTP) sensor 3P
connector.
Turn the ignition switch ON (ll).
69.
70.
11.
Wire side of female terminals

EVAP System
Component Location Index
EVAPORATIVE EMISSION {EVAP)CANISTER VENT SHUT VALVETroubleshooting,step 23 on page 1'l 178,step 1g on page l1- 182
EVAPORATIVE EMISSION IEVAPICANISTER PURGE VALVETroubleshooting,step 3 on page 'l1-175,
step 1on page 11-180
FUEL TANK VAPOR CONTROL VALVETest, page 11'187Replacement, page 11 189
FUEL TANK PRESSURE SENSORTroubleshooting, page 1 1-171
EVAPORATIVE EMISSION {EVAPICANISTERTroubleshooting, step 28 on page 11'183Replacement, page 1 1-189
EVAPORATIVE EMISSION {EVAP}BYPASS SOLENOID VALVETroubleshooting,step 12 on page '11'176,
step '10 on page 11 181
EVAPOBATIVE EMISSON {EVAP)TWO WAY VALVETest, page 'l1-'186
11-170

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