Page 405 of 1395
EVAP PURGE CONTROL SOLENOID VALVE DUTY CONTROLLED AFTER
STARTING ENGINE
ENGINE COOLANT TEMPERATURE ABOVE 154"F (68'C)
Evaporative Emission (EVAP) Controls
Description:
The evaporative emission controls are designed to minimize the amount of fuel vapor escaping to the atmosphere. The
system consists of the following components:
A. Evaporative Emission (EVAPI Control Canister
An EVAP control canister is used for the temporary storage of fuel vapor until the luel vapor can be purged from the
EVAP control canister into the enqine and burned.
B. Vapor Purge ConirolSystem
EVAP control canister purging is accomplished by drawing fresh air through the EVAP control canister and into a pon
on the intake manifold. The purging vacuum is controlled by the EVAP purge control solenoid valve.
C. Fuel Tank Vapor Control System
When fuel vapor pressure in the fuel tank is higher than the set value of the EVAP two way valve, the valve opens and
regulates the flow ot fuel vapor to the EVAP control canister.
'97 model:
EVAPPURGECONTROL
VALVEFromNo. 15BLK/ /ALTERNATORYEL I sP SENSOR r7.s At(in the under-dashfuse/relay box)
VARIOUSSENSORFEESH AIF
BLK
I
FUEI- TANK
(cont'd)
11-203
INTAKE MANIFOLD
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Page 406 of 1395
Emission Gontrol System
Evaporative Emission (EVAP) Controls (cont'dl
'98 - 0O models:
EVAPTHREE WAYVALVE
EVAPCONTROLCANISTERVENT SHUTVALVE
'EL/BLU ._^_-:.*,".. <3|ltAIS"o[..^,
1in the under-dashtuse/relay box)
FrofiBLK/WHT < NO. 15
GRN/BLK
BLU
EVAPBYPASSSOLENOID
EVAP PURGECONTROLSoLENOtOVALVE
L LT GRN/WHT ,
RED/YEL
MANIFOLD
VARIOUSSENSOR
EVAPTWO WAYVALVEVALVE
FUEL TANK
SLK
11-204
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Page 407 of 1395
'97 model:
The scan tool indicates Diagnostic Trouble Code (DTC) P0441: Evaporative Emission (EVAP) control system
insufficient purge flow.
Description
By monitoring the purge line vacuum with the MAP sensor, the PCM can detect insufficient EVAP control system purge
flow.
Possiblo Cause
. EVAP Purge Control Solenoid Valve
. EVAP Purge Control Solenoid Valve Circuit
. EVAP Control Canister
. Vacuum Lines
. PCM
Troubleshooting Flowchart
EVAP PURGE CONTROL
SO1TNOID VALVE 2P
CoNNECTOR (C108)
(v)
YL
Wire side of female
termrnals
(cont'd)
11-205
Th€ MIL has b€en reooited on.DTC P0441 is .tored.
Problem verificationl1. Start the engine. Hold theengine at 3,000 rpm with noload (in Park or neut.al) untilthe radiator fan comes on.2. Do the PCM Reset Procedure.3. Connect the SCS service con-nector,4. Test drive under following con'ditions on the road.- without any electrical load- Transmission in @ or @position- Engine speed between1 ,2OO - 2,4OO rpfi.- Decelerate from 50 mph (80
km/h)to 15 mph (24 km/h)Intermittent trilure, sydern is OKat this time. Check for Door con-nections or loose wir€3 at C108
IEVAP purge control solonoidvalvol .nd at the PCM.
ls DTC P0441 indicated?
Check tor an open in the wire (lcl
linel:1. Turn the ignition switch OFF.2. Disconnect the EVAP purge
control solenoid valve 2P con-nector.3. Turn the ignition switch ON (ll).
4. Measure voltage between bodyground and the EVAP purge
control solenoid valve 2P con-nector terminal No. '1,
R€pafu open in thc wir6 b€tw€enthG EVAP purge control solenoidvalve and the No. 15 ALTEBNA-TOR SP SENSOR (7.5 A)fuse.
ls there batlery voltage?
(To page 11'206)
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Page 408 of 1395
Emission Control System
Evaporative Emission (EVAP) Controls (cont'dl
(From page 11-205)PCM CONNECTOR A (32PI
JUMPER wlRE
PCS IRED/YELI
Wire side of female terminais
PG1 (BLKI
Chsck th6 EVAP purgo controlsolonoid valve:'L Reconnect the EVAP purgecontrol solenoid valve 2P con-nector.2. Connect PCM connector terminals 415 and A10 with a
Chscl to. an op6n or 3hort in th€wiro (PCS lin6):Measure voltage between PCMconnector terminal A15 and bodygrouno,
Does the solenoid valve clickwhen the jumper is connected?
Chock for . .hort in tho wiJe IPCSline):1. Turn the ignition switch OFF.2. Disconnect the PCM connec-tor A (32P).
3. Disconnect the EVAP purge
control solenoid valve 2P con-nector,4. Check for continuity betweenbody ground and PCM con-nector terminal A15.
ls there battery voltage?
Rooair short in tho wir6 bctweenthe EVAP purge control 3olenoidvalvo and tho PCM (A151.
Ropair open in the wir6 betwoonthe EVAP pu]go control .olonoidv.lve end the PCM (A15).
Check the vacuum lin6:Check the vacuum lines of EVAPsystem tor misrouting, leakage,brsakago and clogging.
Are the vacuum lines OK?
(To pago 11'207)
11-206
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Page 409 of 1395
Chack iho EVAP purge controlsolenoid valve:1. Disconnect the vacuum hosetrom the EVAP controlcanister.2, Connect the vacuum pump tothe hose and apply vacuum,
Does it hold vacuum?
Chgck thg EVAP control csnbter:1. Reconnect the vacuum hose tothe EVAP control canister.2. Connect a vac!um gauge tothe purge air hose.3. Connect PCM connector terminals A15 and 410 with ajumper wire.4. Stan the engine.5. Check the vacuum.
Check the EVAP two way valve(see page 11'224).
Does the EVAP two way valvework properly?Rapbce the EVAP two wey valve.
Substitute a known-good PCMand rechock. It symptom/indica-tion gocs away, roplacg tho origi-nrl rcM.
(From page 11-206)
JUMPEF WIRE
<\
EVAP CONTNOLCANISTER
VACUUMPUMPIGAUGE,0-30 in.Hg4973X -
0il1 -
xxxxx
VACUUM/PRESSUREGAUGE0-4 in.Hg07JA2 - ml(x)o8
wire side of female terminals
{cont'd)
-20711
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Page 410 of 1395
Emission Control System
Evaporative Emission (EVAP) Controls (cont'd)
99 - 00 models:
The scan tool indicates Diagnostic Trouble Code {DTC) P0451: The Fuel Tank Pressure sensor circuit range/oerformance Droblem.
ECM/PCM CONNECTORS
SG2 {GRN/BLK)
Wire side of {emaleterminals
FUEL TANKPRESSURESENSOR
VACUUMPUMP/GAUGE.0 -30 in.H9A973X - 041 -
XXXXX
- The MIL har been rooort€d on.- DTC P0451 b storod.
Check lor th6 tu6l tank pr€ssurelen30r:1. Do the ECM/PCM Reset Proce,oure.2. Remove the fuelfill cap.3. Turn the ignition switch ON (ll).4. Monitor the FTP Sensor voltage with the Honda PGMTester, or measure voltagebetween ECM/PCM connectorterminals A29 and C18.
Chock tho vacuum lin6s torrGlriction o. blockago repair asnecessary. lf OK, roplace the fueltank Drer3ur€ sentor.
ls there approx. 2.5 V?
Check for the fuel tank piessureSensot:L Disconnect the hose betweenthe EVAP two way valve andthe fuel tank pressure sensor atthe EVAP two way valve end.2. Connect a vacuum pump tothe open end ofthat hose.3. Turn the ignition switch ON (lll.4. Monitor the FTP S€nsor volt-age with the Honda PGMTester, or measure voltagebetween ECNI/PCNI connectorterminals A29 and C18, andcarefully appiy vacuum on thehose one stroke at a time.5. The voltage should smoothlydrop from the staning approx.2.5 V down to approx. 1.5 V.STOP applying vacuum whenthe voltage drops to approx.1.5 V or damage to the tueltank pressure sensor may
Does the voltage drop to approx.1.5 V and hold?
Intermittent tailuro. sv3tem is OKat this tim€. Chack to. poor con-n€ction6 or 10036 hose at fu6ltank pres3ure ionsor and fueltrnk.
a t32Pl
PTANK ILT GRNI
WAY VALVE
11-208
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Page 415 of 1395
'98 - 00 models:
The scan tool indicates Diagnostic Trouble code (DTC) P1456: Evaporative Emission (EVAP) control system leak
detected {fuel tank system).
Troubleshooting Flowchart
- The MIL has been reported on.- DTC P1456 is stored.
Check the fuel fill cap:Check the fuel fill cap (the caP
must be a gray OEM cap and be
tightened at least three "clicks" toproperly seal the system)-
ls the proper fuel fill cap installed
and properly tightened?Replace or tighton the cap.
Check the lueltill cap seal:
Check the fuel fill cap seal.
Replace the luelfiller pipe.ls the tuel filler pipe damaged?
Fuel till caD is OK. Do the luel
tank pressure Sensor test (see
page 11-2111. (EVAP Purge con-
trol solenoid valve t€sl (see Page11-2151.1r':'99 - 00 models
(cont'd)
11-213
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Page 416 of 1395
Emission Control System
Fuel tank pros3ure sensor tost.(The continuetion of DTC Pl456t.oubls3hooting.,
Chock the tusl trnk pr€3sure sen-sor:1. Remove the fuel fill csp.2. Turn the ignition switch ON fll).3. Monitor the FTP Sensor voh-age with th€ Honda PGMTester, or measure voltagebetween ECM/PCM conn€ctorterminals A29 and C18.
Choct ths vacuum linsr forra3triction o. blockago ropair a!nect*rary. It OK, replaca the fu6ltank praituJc sentot.
ls there approx. 2.5 V?
Check the fuel t nk pressuae 3en-sor:1. Turn the ignition switch OFF.2. Disconnect the hose betweenthe EVAP two way valve andthe tueltank pressure sensor atthe EVAP two way valve end.3. Connect a vacuum pump tothe open end ofthat hose.4. Turn the ignition switch ON 0l).5. Monitor the FTP Sensor volt-age with the Honda PGMTestet, or measure voltagebetween ECM/PCM connectorterminals 429 and C18, andcarefully apply vacuum on thehose one stroke at a lime.6. The voltage should smoothtydrop from the staning approx.2.5 V down to approx. 1.5 V.Stop applying vacuum whenthe voltage drops to approx.1.5 V or damage to the fueltank pressure sensor fiayoccur,
Fu.l tank pressu.c a€nlor b OK.Oo thc EVAP pulge controlsolenoid valve toat (3€€ prgo 11-2151.
Does the voltage drop to approx.1.5 V and hold?
Evaporative Emission (EVAPI Controls (contd)
lP14s6l("ont,a)
ECM/PCM CONNECTORS
SG2 IGRN/BLKI
Wire side oI female terminals
FUEI- TANKPRESSURESENSOR
VACUUMPUMP/GAUGE,0 - 30 in.HgA973X - ill -
xxxxx
EVAP TWOWAY VALVE
11-214
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