1998 HONDA CR-V Rpm sensor

PGM-FI System
Secondary Heated Oxygen Sensor (secondary HO2SI (sensor 2l (cont,d)
lTol3al The scan tool indicates Diagnostic Trouble Code (DTC) P0139: A slow response probtem in the Secondary Heated- Uxygen Sensor (HO2S) (Sensor 2l circuit.
- The MIL has b€en reoorted on.- DTC P0139 is storad.
Probl€m ve.itication:1. Do the ECM/PCM Reset Procedure,Start the engine. Hold theengine at 3,000 rpm with noload (in Park or neutral) untilthe radiator fan comes on.Check the Secondary HO2S(Sonsor 2) output at 3,000 rpmwith the scan tool.
lntehittont failure, 3ystem is OKat this time. Chock for poor con-nections o. loose wi.es at C127(located on ECM/PCM brack€t),C721 {Secondary HO2S, Sensor 2land at the EcM/PcM.
Does the voltage stay within0.3 - 0.6 V for two minutes?
11-120
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Troubleshooting Flowchart
- The MIL has been rePorted on- DTC P0171 andlot P0172 are
stored,
Check the lu6l pressuro regulator
and tusl relum PiPe.ls the lLrel pressure too high
Check lhe Primaty HO2S:1. Start the engine. Hold the
engine at 3,000 rpm with no
load (in Park ot neutral) until
the radiator fan comes on
2. Check the Primary HO2S(Sensor 1) outPut with the
scan tool.
Check lh€ fuel pumP. fuel faedpipe. fuel fiher, and luel Prossurc.eguhior.
Does it stay at lessthan 0.3 V
or more than 0.6 V?
Check for a sticking or leaking
EVAP purge control solenoid
With a vacuum pump, aPPIY vacu
um to the EVAP Purge control
solenoid valve from the intake
manifold side.
Does it hold vacuum?
Check th6 valve clearanc€s and
adjust il necessary. It the valv€
clearances are OK, replace the
fuel iniectors.
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PGM-FI System
Random Misfire
lF()gool", tftod-' and some or lpiogol throughTo3oti
The scan tool indicates Diagnostic Trouble Code (DTC)
P0300*,, P1300*1 and some of po30t - pO3O4; Randommisfire.
Descriotion
Misfire detection is accomplished by monitoring the crankshaft speed with the crankshaft speed fluctuation (cKF) sensorwhich is attached to the crankshaft.lfmisfiring strong enough to damage the catalyst is detected, the MIL will blink during the time of its occurrence, and DTcP0300*', P1300*1 and some of DTCs P03ol through P0304 will be stored. Then, after misfire has ceased, the MtL will comeon,
lf misfiring that increases emissions is detected during two consecutive driving cycles, the MIL will come on, and DTcand some of DTCS p0301 through p0304 wi

be stored.NOTE: lf some of the DTCS listed below are stored at the same time as a misfire DTc, troubleshoot those DTcs first. thentroubleshoot the misfire DTC.
P0106, P]128, P1'129; MAp sensorP0171. P0172; Fuet metering
P0505: ldle Control Svstem
P1336, P1337; CKF sensor
P1361, P1362: TDC sensor
Pl381. Pl382: CYP sensor
P1508: IAC valve *1:,97 model*2: '98 - 00 models
Possiblo Caus€
. Fuel pump insufficient fuel pressure, amountofflow. Fuel line clogging. blockage, leakage. Fuel filter clogginga Fuel pressure regulator stuck open. Distributormalfunction
. lgnition coil wire open, leakage. lgnition control module malfunction. Valves carbon deposita Compression lowa Fuel does not meet Owner's Manual spec., lack offuel
Troubleshooting
By test-driving, determine the conditions during which misfire occurs. Depending on these conditions, test in the orderdescribed in the table below.
Possible cause
[ ;;;;- -....
Crankshaft
speed fluctuation
sensor
Fuel
pressureDistributor and
lgnition wirestcMValve
Clearance
Conditionsection 611-178section 23section 23section 6
Only low rpm and load,6)o
Only acceleratingooo
Only high rpm and loado@,a'@
Not specificationG\o@o@
NOTE: lf misfire doesn't recur, some possible causes are fuel that doesn't meet owner's manual spec, lack of fuel, carbondeposits on spark plu9, etc.
11-126
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PGM-FI System
Knock Sensor {KSl
('99 - 00 models) The scan tool indicates Diagnostic Troublo Code (DTC) P0325: A malfunction in the circuit ofthe Knock Sensor (KS).
ECM/PCM CONNECTOR C 131P}
Wire side of female terminals
KS 1P CONNECTOR IC13?'
KSIRED/BLU)
KS(BED/BLU)
Wire side ol femaletermtnals
ECM/PCM CONNECTORc (31P)
- The MIL has been rooorted on.- DTC m325 is storod.
Problem verification:1. Do the ECM/PCir, Reset Procedure,2. Start the engine. Hold theengine at 3,000 rpm with noload (in Park or neutral) untilthe radiator tan comes on,then let it idle.3. Hold the engine at 3,000 -
4,000 rpm for at least 60 sec-onds,
Intermittent lailu.e, 3ystom is OKat thi3 tim. (te3t drive m.y benacalLrYr.Chock to. poor connsctions olloora wiros rt C137 lknock aon-.o. (KS)) and ar the ECM/FCM.
Ch€ck tor a short in the wir6 {KSlinel:1. Turn the ignition switch OFF.2, Disconnect the knock sensorlP connector.3. Check lor continuity betweenECM/PCM connector terminals C3 and body ground.
Replil rhort in the n irg b6{wocntho ECM/PCM lc:ll and the knocks€ngr1.
Check fo..n open in the wire{KS line):Check for continuity betweenECM/PCM connector terminal C3and knock sensor connector ter,minal No. 1.
B.pair opon in the wirc lrotweenlho ECM/PCM lctl and thc knockacnsor.
ls there cont;nuity?
Substitute a known-good knocksensor and recheck.
ls DTC P0325 indicated?Bcpl.ce the original knock 3€nsor,
Substituto a known-good ECM/PCM and .echeck. lf 3ymptom/indication goes away, replacethe original ECM/PCM.
NOTE: Torque the knock s6nsor to31 N.m (3.2 kgl.m, 23 lbf.ft).
1 1-130
Wire side ot female terminals
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Barometric Pressure (BARO) Sensor
The scan tool indicates Diagnostic Trouble Code (DTC) P1106: A range/performsnce problem in the Barometric
Pressure {BARO) Sensor circuit.
The MIL has been reDorted on.OTC Pl106 b slored.
Problem ve.ification:1. Oo the ECM/PCM reset pro'
ceoure.2. Start the engine. Hold theengine at 3,000 rpm with noload (;n Park or neutral) untilthe radiator lan comes on, thenlet it idle.3. Connect the SCS service con-nector,4. Test'drive with the A/T in Eposition, M/T in 4th gear.
5. Accelerate Ior five secondsusing wide open throttle.
Intermittent fsilure, sy3tom i5 OKat this time.ls DTC P1106 indicated?
Substitute a known-good ECM/PCM .nd recheck. It symptom/indication goes away, replace theorigioal ECM/PCM.
fTiloz l
tP11o8l
The scan tool indicates Diagnostic Trouble Code (DTC) P1107: A low
The scan tool indicates Diagnostic Trouble Code (DTC) Pl108: A
circuit.
voltage problem in the Baro sensor circuit.
high voltage problem in the Baro sensor
- The MIL h.3 b€en roport€d on.- OTC Pl10? or Pl108 i3 stored.
Problom veritic.lion:L Do the ECM/PCM Reset Pro-cedure.2. Turn the ignition switch ON (lli.
Intarmittoni failure, lystom b OKat thb time.ls DTC P1107 or P1108 indicated?
Sub3tituto a known-good ECM/PCM and rcch6ck. ll symptom/indication 9oo3 away. .oplacorho o.igin.l ECM/PCM.
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ldle Control System
System Description
The idle speed of the engjne is controlled by the ldle Air Control (lAC) Valve'
The valve changes the amount of air bypassing into the intake manifold in response to electric current controlled by the
ECM/PCM. When the lAc valve is activated, the valve opens to maintain the proper idle speed.
YEL/ From PGM'FI
BLK TMAIN RELAY
VARIOUSSENSORS
4.
IAC VALVE
INTAKE MANIFOLD
After the engine starts, the IAC valve opens for a certain time. The amount of air is increased to raise the idle speed
about 150 - 300 rpm.
when the cootant temperature ts row, the lAc valve is opened to obtain the proper fast idle speed The amount o{
bvoassed air is thus controlled in relation to the engine coolant temperature
When the idle speed is out o{ specification and the scan tool does not indicate Diagnostic Trouble Code (DTC) P0505
or P1508, check the following items:
. Adjust the idle speed (see page 11-169, 170)
. Air conditioning signal (seepagell-1551
. ALT FR signal (see page 1l-159)
. Starter switch signal (see page 11-16'1)
. A,/T gear position signal (see section 14)
. PSP switch signal (seepagell-162)
. Brake switch signal (see page 11-165)
. Fast idlethermovalve (see page'11 168)
. Hoses and connecttons. IAC valve and its mounting O-rings
lf the above items are normat, suDslitute a known-good IAC valve and readjust the idle speed {see page 11-169, 170)
lf the idle speed still cannot be adjusted to specification (and the scan tool does not indicate DTC P0505 or Pl508)
after IAC valve reolacement, substitute a known-good ECM/PCM and recheck lf symptom goes away' replace the
original ECM/PCM.
11-149
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ldle Control System
ldle Control System
I P0505 | The scan tool indicates Diagnostic T.ouble Code (DTCI PO5O5: ldlecontrol svstem mattunction.
NOTE: lf DTC P1508 is stored at the same time as DTC P0505, troubleshoot DTC P1508 first. then troubleshoot DTC p0505.
Possibls Cause
. IAC valve mechanical malfunction. Throttle body clogged port, improper adlustment. Intake manifold gasket leakaging. Intake air hose loose leakaging. Vacuum hose leakaging
a ECT sensor incorrect output. Throttle Position sensor incorrect output
Troubleshooting Flowchart
The MIL has been reDorted on.DTC P0505 is sto.ed.
Problem verificationi1. Start the engine. Hold theengine at 3,000 rpm with noload (in Park or neutral) untilthe radiator Ian comes on, thenlet it idle.2. With the scan tool, check thelollowing items.- Throttle position should beapprox. 10% with the throt-tle {ully closed.- Engine coolant temperature shorJld be 194 - 205'F(90 - 96"C).lf they are not within thespec., repair the faulty sen-sor circuit.3 Check the engine speed atidle with no-load conditions:headlights, blower fan. reardefogger, radiator lan, and airconditioner are not operaling,
Inte.mittent failure. syltem is OKat this time.ls it 750 {730)* i 50 rpm?
ls il 700 (680)' rpm or less?
{To page 11-151)(To page 1'l-151)
l:'99 - 00 models
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Emission Control System
Three Way Catalytic Converter {TWCI (cont'd}
1P0420 Thescantool indicates Diagnostic Trouble Code (DTC) P0420: Catalyst system efficiency belowthreshold.
DescriDtion
This system evaluates the catalyst's capacity by means of the HO2S (Primary and Secondary) output during stable driving
conditions. lf deterioration has been detected during three consecutive driving cycles, the MIL comes on and DTC P0420 will
be stored.
NOTE: lf some of the DTCS listed below are stored at the same time as DTC P0420, troubleshoot those DTCS first. then
troubleshoot DTC P0420.
P0137, P0138: Secondary HO2S (Sensor 2)
P0141: Secondary HO2S (Sensor 2) Heater
Possible Cause
. IWC Deterioration
. Exhaust system leakage
Troubleshooting Flowchart
- The MIL has been reDoried on.- DTC P0420 is stored.
Problem verification:1. Do the ECM/PCM Reset Procedure,2. Start the engine. Hold theengine at 3,000 rpm with noload (in Park or neutrali untilthe radiator fan comes on.3. Connect the SCS service connector.4. Test-drive 40 - 55 mph (64 - 88km/h) for approx. lwo minutes.Then decelerate for at least 3seconds with the throftle completely closed. Then reducethe vehicle speed to 35 mph
156 km/h), and try to hold ituntil the readiness code
Intermittent tailure. system is OKat this time.ls DTC P0420 indicated?
Check the TWC (see section 9).lI nocessary, replace the TwC.
11-200
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