Your Vehicle: 2001 Ford Escort ZX2 L4-2.0L DOHC VIN 3
Vehicle » Powertrain Management » Computers and Control Systems » Testing and Inspection » Symptom Related Diagnostic Procedures » Step 3: No DTC(S) Present Symptom Charts  
  Step 3: No DTC(S) Present Symptom Charts  

Step 3: No DTC(s) Present Symptom Charts

Chart 1

  • Starting Concerns: Stalls After Start
  • Stalls/Quits: Idle, Acceleration, Cruise
  • Runs Rough
  • Misses
  • Buck/Jerk
  • Hesitation/Stumble
  • Surge
  • Unique Idle concerns: Rolling Idle

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


Chart 2

Starting Concerns

  • Hart Start/Long Crank
  • Erratic Start/Erratic Crank


Chart 3

Starting Concerns:

  • No Start, Normal Crank

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:

  • Slow Return To Idle


Chart 5

Unique Idle Concerns:

  • Fast Idle

Additional Driveability Concerns:

  • 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 applicable wiring diagram and/or service procedure.


Chart 6

Unique Idle Concerns:

  • Low/Slow Idle


  • Deceleration


Chart 7



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 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 in-depth diagnosis. Also, the following external factors could contribute to "poor fuel economy" conditions:

  • Stop/go driving
  • Improper tire pressure/size
  • Vehicle loads (such as trailer towing)
  • Extended winter warm-up conditions
  • High speed driving
  • Improper axle ratio
  • Road/weather conditions
  • Aftermarket add-ons
  • Short run operations
  • Customer expectations


Chart 11

Emission Compliance


Chart 12

Warning Indicators:

  • NIL
  • TCIL
  • SIL
  • Temperature Warning Indicator Lamp or Gauge (applications with CHT sensor)
  • Check Fuel Cap Indicator Lamp


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


Chart 13

Automatic Transmission Concerns:

  • Upshift
  • Downshift
  • Engagement


Chart 14


  • Tachometer Inoperative
  • Speedometer Inoperative


Chart 15

Oil System Concerns:

  • High Oil Consumption
  • Leaks


Chart 16

Cooling System Concerns

  • Electric Cooling Fan (s) Does Not Operate (Low, Medium and/or High Speed)
  • Hydraulic Cooling Fan Does Not Operate (LS6/8)


Chart 17

Cooling System Concerns:

  • Electric or Hydraulic Cooling Fan(s) Always Runs

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


Chart 18

Exhaust System Concerns:

  • 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:

  • 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 Symptom Index (for noise such as spark knock) or applicable Workshop Manual section.


Chart 21

Climate Control:

  • Lack of Cooling (A/C)/ A/C Not Functioning
  • A/C Always On
  • A/C Compressor Runs Continuously
  • A/C Does not CUT-OFF Under WOT Conditions (Mustang only)


Chart 22

Exhaust System Concern:

  • 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.