On Board Diagnostics II PCED

1999 PCED On Board Diagnostics II

SECTION 5: Pinpoint Tests

EM: Emissions Compliance

EM: Introduction

EM1 ANALYZE VEHICLE'S INSPECTION AND MAINTENANCE (I/M) TEST REPORT

Analyze I/M test report for data entry errors:

Correct model and year.
Correct test weight, if included on report (this number will be less than the vehicle's GVW).
Correct calibration, if included on report (such as Calif. or Federal).

Analyze I/M test report results:

Identify which gas readings are high AND which readings are low.
For reports that include a drive trace, identify during which mode the gas(es) failed. Be aware that if all gases were high early then decreased, the catalyst may have been cool when testing began.

Has the I/M test report been analyzed?

Yes	No
GO to EM2 .	REPEAT this test step.

EM2 DID THE VEHICLE FAIL ONLY AN EVAP SYSTEM LEAK TEST OR A PURGE FLOW TEST (if these tests were performed)?

Did the vehicle fail only an EVAP system leak test or purge flow test (all gases OK)?

Yes	No
EVAP concern only. GO to EM35 .	GO to EM3 .

EM3 BASELINE VEHICLE

Note: Baselining the vehicle's exhaust gas readings is important so the baseline readings can be used for comparison after any repair is made.

Baseline vehicle using an exhaust gas analyzer. If the vehicle must be driven, be certain any baseline drive used is repeatable. The same drive cycle will be used to verify any repair.
During the baseline, check for any related symptoms that may be present (such as driveability, transmission shifting or exhaust smoke concerns).

Has the vehicle been baselined?

Yes	No
GO to EM4 .	REPEAT this test step.

EM4 CHECK IF ANY OTHER SYMPTOMS ARE PRESENT

Are any of the following symptoms present?

Driveability Concerns (including Idle or Transmission Concerns).
Exhaust smoke.
Cooling System Concerns (engine not operating at proper temperature)

Yes	No
GO to Section 3 (begin at Step 1: PCM Quick Test) for direction to repair the additional symptom. Also REFER to the Exhaust Gas Analysis Chart at the beginning of this pinpoint test for additional information. After any repair, RETURN to EM40 to verify repair.	No other concerns present. GO to EM5 .

EM5 PRELIMINARY CHECKS

Perform the following preliminary checks:

Vacuum lines (leaks/blockage).
Electrical connections.
Proper scheduled maintenance.
Intake air tube and air cleaner concerns (such as obstructions, leaks or dirty air cleaner element).
Ford authorized emission controls and components installed on vehicle.

Are all checks OK?

Yes	No
GO to EM6 .	REPAIR as necessary. After repair, GO to EM40 to VERIFY repair.

EM6 PERFORM PCM QUICK TEST

Complete a PCM Quick Test to access any PCM DTCs (Refer to Section 3 , Step 1: PCM Quick Test [for Test Step procedure only]).

Is a fault indicated?

Yes	No
FOLLOW Section 3 Quick Test direction. After repair, RETURN to EM40 to verify repair.	GO to EM7 .

EM7 CHECK CARBON MONOXIDE (CO) LEVELS

Did the vehicle have excessive CO levels?

Yes	No
Excessive CO levels indicate that the engine is running rich. GO to EM15 .	GO to EM8 .

EM8 CHECK HYDROCARBON (HC) LEVELS

Did the vehicle have excessive HC levels?

Yes	No
Excessive HC levels with low to normal CO levels indicate that the engine is running lean. GO to EM25 .	GO to EM9 .

EM9 CHECK OXIDES OF NITROGEN (NOx) LEVELS

Did the vehicle have excessive NOx levels?

Yes	No
GO to EM30 .	VERIFY all previous testing.

EM15 HIGH CO LEVELS: CHECK HC LEVELS

Did the vehicle have excessive HC levels?

Yes	No
GO to EM16 (to check for incomplete combustion/running rich).	GO to EM17 (to check for running rich).

EM16 CHECK SECONDARY IGNITION SYSTEM

Go to Pinpoint Test Step JB1 to check the secondary ignition system.

Is a fault indicated?

Yes	No
FOLLOW Pinpoint Test direction. After repair, RETURN to EM40 to verify repair.	GO to EM17 .

EM17 CHECK FUEL DELIVERY SYSTEM FOR CONCERNS SUCH AS HIGH FUEL PRESSURE AND ABILITY TO HOLD PRESSURE

For Natural Gas applications:

Go to Pinpoint Test Step HB1 .

All others:

Go to Pinpoint Test Step HC1 .

Is a fault indicated?

Yes	No
FOLLOW Pinpoint Test direction. After repair, RETURN to EM40 to verify repair.	GO to EM18 .

EM18 CHECK PCV SYSTEM FOR LEAKS, STUCK VALVE, ETC.

Go to Pinpoint Test Step HG1 to check the PCV System.

Is a fault indicated?

Yes	No
FOLLOW Pinpoint Test direction. After repair, RETURN to EM40 to verify repair.	GO to EM19 .

EM19 CHECK EXHAUST SYSTEM

Go to Pinpoint Test Step HF1 to check the exhaust system.

Is a fault indicated?

Yes	No
FOLLOW Pinpoint Test direction. After repair is performed, RETURN to EM40 to verify repair.	GO to EM20 .

EM20 CHECK BASE ENGINE

Go to Engine System—General Information Section 303-00 in the Workshop Manual to check for proper compression, valvetrain, camshaft, etc.

Is a fault indicated?

Yes	No
REPAIR as required according to Workshop Manual direction. After repair, RETURN to EM40 to verify repair.	GO to EM21 .

EM21 ADDITIONAL CHECKS

Additional checks:

Incorrect PCV valve.

Are all checks OK?

Yes	No
GO to EM45 .	REPAIR as necessary. After repair, GO toEM40 to verify repair.

EM25 HIGH HC WITH NORMAL TO LOW CO LEVEL: CHECK FUEL DELIVERY SYSTEM FOR CONCERNS SUCH AS LOW FUEL PRESSURE

For Natural Gas applications:

Go to Pinpoint Test Step HB1 .

All others:

Go to Pinpoint Test Step HC1 .

Is a fault indicated?

Yes	No
FOLLOW Pinpoint Test direction. After repair, RETURN to EM40 to verify repair.	GO to EM26 .

EM26 CHECK SECONDARY IGNITION SYSTEM

Go to Pinpoint Test Step JB1 to check the secondary ignition system.

Is a fault indicated?

Yes	No
FOLLOW Pinpoint Test direction. After repair, RETURN to EM40 to verify repair.	GO to EM27 .

EM27 CHECK PCV SYSTEM

Go to Pinpoint Test Step HG1 to check the PCV system.

Is a fault indicated?

Yes	No
FOLLOW Pinpoint Test direction. After repair, RETURN to EM40 to verify repair.	GO to EM28 .

EM28 CHECK BASE ENGINE

Go to Engine System—General Information Section 303-00 in the Workshop Manual to check base engine for concerns such as intake manifold leaks, improper compression, valvetrain or camshaft damage.

Is a fault indicated?

Yes	No
REPAIR as required according to Workshop Manual direction. After repair, RETURN to EM40 to verify repair.	GO to EM29 .

EM29 ADDITIONAL CHECKS

Additional checks:

Incorrect PCV valve.

Are all checks OK?

Yes	No
GO to EM45 .	REPAIR as necessary. After repair, GO to EM40 to verify repair.

EM30 HIGH NOx WITH NORMAL TO LOW HC AND CO LEVELS: CHECK BASE ENGINE FOR CONCERNS SUCH AS EXCESSIVE CARBON BUILD UP IN COMBUSTION CHAMBER

Go to the Engine System—General Information Section 303-00 in the Workshop Manual to check for base engine concerns such as excessive carbon build up in the combustion chamber.

Is a fault indicated?

Yes	No
REPAIR as required according to Workshop Manual direction. After repair, RETURN to EM40 to verify repair.	GO to EM31 .

EM31 ADDITIONAL CHECKS

Additional checks:

Transmission torque converter clutch operation.
Cooling System concerns (such as aftermarket front fascia covering intake air, intake air system modifications).
Engine running lean (concerns such as vacuum leaks, low fuel pressure [ refer to steps starting at EM25 ]).

Are all checks OK?

Yes	No
GO to EM45 .	REPAIR as necessary. After repair, GO to EM40 to verify repair.

EM35 EVAP SYSTEM CONCERN: PRELIMINARY CHECKS

Analyze I/M Test Report to determine when concern is present. Attempt to verify concern.
Make the following preliminary checks:

Fuel filler cap (check for proper installation, physical damage or contamination).
EVAP system lines/hoses (check for proper connections, damage or blockage).
Fuel vapor storage canister damage.

Are all checks OK?

Yes	No
GO to EM36 .	REPAIR as necessary. After repair, GO to EM38 to verify repair.

EM36 PERFORM PCM QUICK TEST

Complete PCM Quick Test to access any PCM DTCs (Refer to Section 3 , Step 1: Quick Test [for Test Step procedure only]).

Is a fault indicated?

Yes	No
FOLLOW Section 3 Quick Test direction. After repair, RETURN to EM38 to verify repair.	GO to EM37 .

EM37 CHECK EVAP SYSTEM

Go to Pinpoint Test StepHX44 .

Is a fault indicated?

Yes	No
FOLLOW Pinpoint Test direction. After repair, RETURN to EM38 to verify repair.	VERIFY test results. If OK, GO to Pinpoint Test Step Z1 , or RETURN to Section 3 to repair any additional symptoms. After any repair, RETURN to EM38 to verify repair.

EM38 EVAP SYSTEM REPAIR VERIFICATION

Vehicle repair performed.
Reset the PCM Keep Alive Random Access Memory (RAM). Be aware that this will set DTC P1000 (and reset the On-Board System Readiness Test).
To relearn some basic Adaptive Learning (trim) values, run the engine at 2500 rpm for one minute and idle engine for two minutes.
Rerun PCM Quick Test (refer to Section 3 , Step 1: PCM Quick Test). REPAIR any DTCs as directed.
Perform the EVAP system leak test and flow check.

Does the vehicle pass the EVAP system leak test and flow check?

Yes	No
Save any repair documentation that may be required by local/federal laws. RETURN vehicle to customer.	Original concern not repaired, or another concern exists. RETURN to EM1 and proceed as directed.

EM40 REPAIR VERIFICATION

Vehicle repair completed.
Reset the PCM Keep Alive Random Access Memory (RAM). Be aware that this will set DTC P1000 (and reset the On-Board System Readiness Test).
To relearn some basic Adaptive Learning (Trim) values, run the engine at 2500 rpm for one minute and idle engine for two minutes.
Rerun PCM Quick Test (refer to Section 3 , Step 1: PCM Quick Test). REPAIR any DTCs as directed.
Again perform the baseline test using the exhaust gas analyzer.

Note: If vehicle needs to be driven for the baseline, it may be necessary to drive the vehicle first for up to 8 km (5 miles) to relearn some additional Adaptive Learning (trim) values. Also, during the baseline be certain to use the same drive mode that was used for the original baseline test (refer to EM3 ).

For I/M 240 Emission Testing areas (original gas concentrations reported in Grams Per Mile):

Refer to the beginning of this pinpoint test for information on verifying an excessive Grams Per Mile indication using a Parts Per Million (PPM) reading.

All others (original gas concentrations reported in Parts Per Million):

Verify gas levels are within acceptable range.

Are all gases within the acceptable range?

Yes	No
SAVE any repair documentation that may be required by local/federal laws. RETURN vehicle to customer.	Gas level is still high, or another gas level is above the acceptable range: RETURN to step EM1 and proceed as directed.

EM45 CATALYST DELTA TEMPERATURE TEST

All previous testing as indicated completed.
Disable the AIR system, if equipped.
Run the engine for two minutes at 2500 rpm to heat the exhaust system.
Key OFF.
Disconnect and ground one spark plug wire from each cylinder bank (for Coil On Plug applications, disconnect coil connector).
Start engine and run at 1000 rpm.
Disconnect IAC valve (maintain 1000 rpm).
Measure the surface temperature of both the inlet and outlet of each under-body catalytic converter using an infrared temperature probe.
Compare the difference in temperature between the inlet and outlet readings of each under-body catalytic converter.

Does each catalytic converter have a difference of more than 28° C (50°F) between its inlet and outlet reading?

Yes	No
The catalytic converter(s) is operating correctly. RECONNECT spark plug wire(s), IAC valve and AIR system (if equipped). COMPLETE PCM Reset to clear any DTC(s) set during testing. VERIFY previous test results. If OK, GO to Pinpoint Test Step Z1 , or RETURN to Section 3 to repair any additional symptoms. After any repair is completed, RETURN to EM40 to verify repair.	For the catalytic converter(s), that had less than 28° C (50°F) difference, testing indicates the catalytic converter is not working. REPEAT test step to verify results. If the temperature difference is still less than required, REPLACE the catalytic converter. RESTORE vehicle. GO to EM40 to verify repair.