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 customer to turn engine off while refueling to avoid contamination or damage to the EVAP system.

SYSTEM/COMPONENT	REFERENCE ( PINPOINT TEST - CNG, FLEX-FUEL & GASOLINE ) unless noted
Check The Following PIDs: DPFEGR (if equipped) (hot idle value within 0.15V of KOEO value) LONGFT1 / LONGFT2 (value between -20 and +20) VPWR (value between 10.5 and 17.0 volts, and within 0.5 volts of battery voltage)	DPFEGR PID value not within 0.15V of KOEO value: For vehicles equipped with ESM EGR: GO to H: Exhaust Gas Recirculation System Module (ESM) STEP HH34. All others: GO to E: Exhaust Gas Recirculation (EGR) Systems STEP HE57. LONGFT1 / LONGFT2 value low (-): Continue diagnosis. Concentrate checks in areas that would cause the engine to run rich. LONGFT1 / LONGFT2 value high (+): Continue diagnosis. Concentrate checks in areas that would cause the engine to run lean. VPWR not between 10.5 and 17.0 volts: Go to the appropriate GENERATORS & REGULATORS article. VPWR between 10.5 and 17.0 volts, but not within 0.5 of battery voltage: CHECK B(+) supply to PCM power relay (or CCRM). CHECK VPWR circuit between PCM and PCM power relay or CCRM. CHECK PWR GND circuits.
For vehicles that run rough at idle: With the key on, engine off, check the INJxF PIDs (the "x" indicates the injector number, there will be one INJxF PID for each engine cylinder). All INJxF PIDs must indicate no fault (or NO).	INJxF PID(s) indicate a fault (an injector circuit fault is indicated): Natural Gas applications: GO to A: Natural Gas Fuel Control STEP HA27. All others: GO to H: Fuel Control STEP H46.
Mass Air Flow (MAF) Sensor	GO to C: Mass Air Flow Sensor STEP DC25.
Secondary Ignition System	For vehicles equipped with a coil pack ignition system, GO to PINPOINT TEST JC . For all others, GO to PINPOINT TEST JB .
Fuel Delivery System	Natural Gas Applications: GO to B: Natural Gas Fuel Delivery System STEP HB1. All Others: GO to C: Fuel Delivery System STEP HC1.
Exhaust System	GO to F: Catalyst Efficiency Monitor and Exhaust Systems STEP HF5.
PCV System	GO to G: Positive Crankcase Ventilation (PCV) System STEP HG1.
Natural Gas applications with rough idle: Injector circuits between NG module and injectors.	GO to A: Natural Gas Fuel Control STEP HA27.
EVAP System	GO to X: Evaporative Emission (EVAP) Monitor and System STEP HX14.
Automatic Transmission	Automatic Transaxle/Transmission - Refer to the appropriate AUTOMATIC TRANSMISSION article.
Base Engine	Engine System - Refer to the appropriate ENGINE article.
Intake Air System	GO to U: Intake Air Systems STEP HU1.
Applications with A/C Pressure Sensor (3 wire sensor): A/C pressure (ACP) sensor input to PCM	GO to S: Air Conditioning Pressure (ACP) Sensor STEP DS18.
Additional Testing	GO to Z: Intermittent STEP Z1.
Additional Checks: NOTE: Some applications have a PID that will indicate whether the PCM is reducing torque (TQ_CNTL) (#095E b0), and if so, why the torque is being reduced (#095Eb1-13) (0 = No torque reduction requested; 1 = Torque Truncation. Cuts fuel to protect when line pressure fails to minimum limit; 2 = Traction Control Event. Cuts fuel and/or spark for traction control; 3 = Vehicle Speed Limit - Cuts fuel). Correct PCM vehicle identification (VID) block information (refer to FLASH ELECTRICALLY ERASABLE PROGRAMMABLE READ ONLY MEMORY - FLASH EEPROM . Be aware of engine RPM/speed limiting functions of the PCM (look for incorrect high vehicle speed signal from ABS, VSS or OSS) Verify fuel cap is properly tightened, and not physically damaged. Drivelines Manual transmission/clutch Charging System Traction control system (if equipped) A/C system (for surge with A/C on) Speed control system (for surge with speed control on) A/C compressor diode, if equipped (for rolling idle)	Appropriate service information article.