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Problem Symptoms Table

HINT:

Use the table below to help determine the cause of the problem symptoms. The potential causes of the symptoms are listed in order of probability in the "Suspected area" column of the table. Check each symptom by checking the suspected areas in the order they are listed. Replace parts as necessary.

SFI system 

PROBLEM SYMPTOMS CHART

Symptom Suspected Area Reference
Engine does not crank (does not start)
  • Starter
STARTER
  • Starter relay
STARTER RELAY
  • Ignition switch
IGNITION SWITCH
  • VC Output Circuit
VC OUTPUT CIRCUIT 
No initial combustion (does not start)
  • ECM power source circuit
ECM POWER SOURCE CIRCUIT 
  • VC Output Circuit
VC OUTPUT CIRCUIT 
  • Fuel pump control circuit
FUEL PUMP CONTROL CIRCUIT 
  • ECM
ECM 
Engine cranks normally (difficult to start)
  • Fuel pump control circuit
FUEL PUMP CONTROL CIRCUIT 
  • Compression
ON-VEHICLE INSPECTION
Cold engine (difficult to start)
  • Starter signal circuit
DTC P0617 STARTER RELAY CIRCUIT HIGH 
  • Fuel pump control circuit
FUEL PUMP CONTROL CIRCUIT 
  • Spark plug
ON-VEHICLE INSPECTION
  • Ignition system
ON-VEHICLE INSPECTION
  • Injector
FUEL INJECTOR
Hot engine (difficult to start)
  • Starter signal circuit
DTC P0617 STARTER RELAY CIRCUIT HIGH 
  • Fuel pump control circuit
FUEL PUMP CONTROL CIRCUIT 
  • Spark plug
ON-VEHICLE INSPECTION
  • Ignition system
ON-VEHICLE INSPECTION
  • Injector
FUEL INJECTOR
High engine idle speed
  • A/C signal circuit (compressor circuit)
COMPRESSOR CIRCUIT
  • ECM power source circuit
ECM POWER SOURCE CIRCUIT 
  • Electronic throttle control circuit
ECM POWER SOURCE CIRCUIT 
  • Air induction system
IACV CONTROL CIRCUIT 
  • PCV hose
-
Low engine idle speed
  • A/C signal circuit (compressor circuit)
COMPRESSOR CIRCUIT
  • Fuel pump control circuit
FUEL PUMP CONTROL CIRCUIT 
  • Electronic throttle control circuit
DTC P2102 THROTTLE ACTUATOR CONTROL MOTOR CIRCUIT LOW; DTC P2103 THROTTLE ACTUATOR CONTROL MOTOR CIRCUIT HIGH 
  • Air induction system
IACV CONTROL CIRCUIT 
  • PCV hose
-
Rough idling
  • Compression
ON-VEHICLE INSPECTION
  • Fuel pump control circuit
FUEL PUMP CONTROL CIRCUIT 
  • Electronic throttle control system
DTC P2102 THROTTLE ACTUATOR CONTROL MOTOR CIRCUIT LOW; DTC P2103 THROTTLE ACTUATOR CONTROL MOTOR CIRCUIT HIGH 
  • Air induction system
IACV CONTROL CIRCUIT 
  • PCV hose
-
Hunting (when idling)
  • ECM power source circuit
ECM POWER SOURCE CIRCUIT 
  • Fuel pump control circuit
ECM POWER SOURCE CIRCUIT 
  • Spark plug
ON-VEHICLE INSPECTION
  • Ignition system
ON-VEHICLE INSPECTION
  • Injector
FUEL INJECTOR
  • Electronic throttle control system
DTC P2102 THROTTLE ACTUATOR CONTROL MOTOR CIRCUIT LOW; DTC P2103 THROTTLE ACTUATOR CONTROL MOTOR CIRCUIT HIGH 
  • Air induction system
IACV CONTROL CIRCUIT 
  • PCV hose
-
Hesitation / Poor acceleration (poor driveability)
  • Fuel pump control circuit
FUEL PUMP CONTROL CIRCUIT 
  • Spark plug
ON-VEHICLE INSPECTION
  • Ignition system
ON-VEHICLE INSPECTION
  • Injector
FUEL INJECTOR
Surging (poor driveability)
  • Fuel pump control circuit
FUEL PUMP CONTROL CIRCUIT 
  • Spark plug
ON-VEHICLE INSPECTION
  • Ignition system
ON-VEHICLE INSPECTION
  • Injector
FUEL INJECTOR
Engine stalls soon after starting
  • Fuel pump control circuit
FUEL PUMP CONTROL CIRCUIT 
  • Spark plug
ON-VEHICLE INSPECTION
  • Ignition system
ON-VEHICLE INSPECTION
  • Injector
FUEL INJECTOR
Engine stalls during A/C operation
  • A/C signal circuit (compressor circuit)
COMPRESSOR CIRCUIT
  • ECM
ECM 
Usable / difficult to refuel
  • Refueling valve (canister)
CANISTER