Engine Controls - Symptom Charts - Cng, Flex-Fuel & Gasoline Ford Crown Victoria II

QT1 PERFORM PCM QUICK TEST

Note. If the vehicle was brought in with an emission compliance failure symptom, GO to M: Emission Compliance STEP EM1.

1. Complete preliminary checks looking for obvious concerns that may relate to the symptom. Check items such as those listed: Related electrical connectors or fuses Vacuum lines (leaks, routing) Air intake system (leaks, restrictions) Fuel quality (octane, contamination, winter/summer blend) Cooling system (engine operating at proper temperature)
2. Access any related TSB information (if available).
3. Complete PCM Quick Test to access any DTCs. Note any Key On Engine Off, Key On Engine Running (if engine runs) and Continuous Memory (MIL and non-MIL) DTCs.

Note. If unable to access DTCs, or any scan tool communication concern exists, GO to A: Unable to Activate Self-Test/Network Communication Error/DTC P1001 STEP QA1. For additional information on retrieving MIL and non-MIL DTCs, refer to CONTINUOUS MEMORY SELF-TEST .

Were any DTCs present?

QT2 ENGINE RUNS ROUGH AT IDLE WITH KEY ON ENGINE RUNNING OR CONTINUOUS MEMORY DTC(s): CHECK INJECTOR FAULT (INJxF) PID(s)

Note. An injector circuit fault could result in unrelated DTC(s) being received from the PCM.

1. Key on, engine off.
2. Access the INJxF PIDs (the "x" indicates the injector number). There will be one INJxF PID for each engine cylinder.

Do any of the INJxF PIDs indicate a fault (or Yes)?

Step 2: No DTC(s) Present Symptom Chart Index

DRIVEABILITY

DRIVEABILITY - PERFORMANCE WHILE DRIVING CONCERNS

ADDITIONAL DRIVEABILITY CONCERNS

ELECTRICAL

ENGINE

DRIVELINE

Chart 1

1. Starting Concerns: Stalls After Start
2. Stalls/Quits: Idle, Acceleration, Cruise
3. Runs Rough
4. Misses
5. Buck/Jerk
6. Hesitation/Stumble
7. Surge
8. Unique Idle concerns: Rolling Idle

Note. For stalls on passenger car applications, engine may stall if left running while refueling. Advise customer to turn engine off while refueling to avoid contamination or damage to the EVAP system.

Chart 2

Starting Concerns

1. Hard Start/Long Crank
2. Erratic Start/Erratic Crank

Chart 3

Starting Concerns

1. No Start (engine cranks)

Note. Extended cranking because of a no start can load the exhaust system with raw fuel, damaging the catalytic converter after the engine starts. For applications with Secondary Air Injection (AIR) Systems, perform the following after the no start has been repaired: Disconnect the electric secondary air injection (AIR) solid state relay, run the engine until the surplus fuel is used up, and reconnect the relay (disconnecting the relay may set a Continuous Memory PCM DTC that will need to be cleared).

Chart 4

Unique Idle Concerns

1. Slow Return To Idle

Chart 5

Unique Idle Concerns

1. Fast Idle

Additional Driveability Concerns

1. Diesels/Runs On

Note. If vehicle runs normally after the ignition key is turned OFF, check for damaged ignition switch, IGN RUN circuit short to power, VPWR circuit short to power, etc. Refer to the appropriate SYSTEM WIRING DIAGRAMS article.

Chart 6

Unique Idle Concerns

1. Low/Slow Idle

Stalls/Quits

1. Deceleration

Chart 7

Backfires

Chart 8

Lack/Loss of Power

Note. Verify symptom is reported under normal driving conditions without excessive engine/vehicle load. Also, be aware of the engine rpm/speed limiting functions of the PCM.

Note. For applications with knock sensor, a lack of power may result when the vehicle is operated with a breakout box installed at the PCM. The KS circuits are not shielded in the breakout box, and KS signal noise may be noticed by the PCM. If this happens, spark timing will be retarded and a lack of power may result.

Chart 9

Spark Knock

Chart 10

Poor Fuel Economy

Note. Since driving styles can have a significant influence on fuel economy, verify the concern before starting an indepth diagnosis. Also, the following external factors could contribute to "poor fuel economy" conditions

1. Stop/go driving
2. Improper tire pressure/size
3. Vehicle loads (such as trailer towing)
4. Extended winter warm -up conditions
5. High speed driving
6. Improper axle ratio
7. Road/weather conditions
8. Aftermarket add-ons
9. Short run operations
10. Customer expectations

Chart 11

Emissions Compliance

Chart 12

Warning Indicators

1. MIL
2. TCIL
3. Temperature Warning Indicator Lamp or Gauge (applications with CHT sensor)
4. Check Fuel Cap Indicator Lamp

Note. If the symptom is both "MIL on" AND "exhaust emission test failure", GO directly to CHART 11 . If engine is a no start, GO directly to CHART 3 . If engine runs rough at idle, GO directly to CHART 1 .

Chart 13

Automatic Transmission Concerns

1. Upshift
2. Downshift
3. Engagement

Chart 14

Instrumentation

1. Tachometer Inoperative
2. Speedometer Inoperative
3. Boost Gauge indicates higher than normal boost (supercharger applications)
4. Fuel Gauge Inoperative

Chart 15

Oil System Concerns

1. High Oil Consumption
2. Leaks

Chart 16

Cooling System Concerns

1. Electric Cooling Fan(s) Does Not Operate (Low, Medium, High or Variable speed))

Chart 17

Cooling System Concerns

1. Electric Cooling Fan(s) Always Runs

Note. This chart is intended to only diagnose an electric cooling fan that always runs with a "cool" engine and the A/C and defroster off.

Chart 18

Exhaust System Concerns

1. Smoke

Note. Black smoke indicates a rich fuel mixture, blue smoke indicates burning oil, and white smoke indicates water in the combustion chamber.

Chart 19

Fuel System Concerns

1. Odor, Engine Compartment

Chart 20

Engine Noise (under hood)

Note. Attempt to identify source of noise. If noise is from source other than those listed below, refer to STEP 2: NO DTC(S) PRESENT SYMPTOM CHART INDEX (for noise such as spark knock) or the appropriate service information article.

Chart 21

Climate Control

1. Lack of Cooling (A/C)/ A/C Not Functioning
2. n A/C Always On
3. A/C Compressor Runs Continuously
4. A/C Does Not CUT-OFF Under WOT Conditions (Mustang only)

Chart 22

Exhaust System Concerns

1. Odor (Sulfur, Rotten Egg Smell)

Note. A slight sulfur smell may be normal. Catalysts with less than 8,000-16,000 kilometers (5,000-10,000 miles) (new vehicle or replaced catalyst) are likely to have a sulfur smell due to the highly active state of new catalysts. Replacing the catalyst can actually make the symptom worse.

Chart 23

Starting Concerns

1. No Crank

See also:
• M: Emission Compliance
• CONTINUOUS MEMORY SELF-TEST
• DIAGNOSTIC TROUBLE CODE (DTC) CHARTS
• FLASH ELECTRICALLY ERASABLE PROGRAMMABLE READ ONLY MEMORY - FLASH EEPROM
• QT2
• STEP 2: NO DTC(S) PRESENT SYMPTOM CHART INDEX
• QT1
• CHART NUMBER: 2
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• CHART NUMBER: 13