Symptom Chart

CAUTION: When probing connectors to take measurements in the course of the pinpoint tests, use the adaptor kit, part number 3548-1358-00.

NOTE: When performing electrical voltage or resistance tests, always use a digital multimeter (DMM) accurate to 3 decimal places, and with an up-to-date calibration certificate. When testing resistance, always take the resistance of the DMM leads into account.

NOTE: Check and rectify basic faults before beginning diagnostic routines involving pinpoint tests.

Symptom Chart

Symptom	Possible source	Action
Engine cranks, but does not fire	Engine breather system disconnected/restricted Ignition system Fuel system Harness CKP sensor ECM fault	Check engine breather system, Refer to Engine Emission Control article. For ignition system, Refer to Engine Ignition article. Check fuel pressure, refer to pinpoint tests in this section. For CKP tests, Refer to Electronic Engine Controls article. Contact Dealer technical support for advice on possible ECM failure.
Engine cranks and fires, but will not start	Purge valve Fuel pump Coolant temperature sensor Spark plugs Check for water ingress into spark plug wells (SC only) HT short to ground (tracking) check rubber boots for cracks/damage Ignition coil failure(s) Harness	For evaporative emissions components, Refer to Evaporative Emissions article. Check fuel pressure. For ECT sensor tests, Refer to Electronic Engine Controls article. For ignition system Refer to Engine Ignition article.
Difficult to start cold	Check coolant anti-freeze content Battery CKP sensor EGR valve stuck open Fuel pump Coolant temperature sensor Purge valve	For battery information, Refer to Battery, Mounting and Cables article. For CKP sensor tests, Refer to Electronic Engine Controls article. For EGR system information, Refer to Engine Emission Control article. Check fuel pressure. For ECT sensor tests, Refer to Electronic Engine Controls article. For evaporative emissions components, Refer to Evaporative Emissions article.
Difficult to start hot	Injector leak Fuel temperature sensor IAT sensor MAF sensor Purge valve Fuel pump Ignition system Coolant temperature sensor EGR valve stuck open	Refer to Fuel Injector - Removal and Installation . For fuel temperature sensor, IAT sensor and MAF sensor tests, Refer to Electronic Engine Controls article. For evaporative emissions components, Refer to Evaporative Emissions article. Check fuel pressure. For ignition system, Refer to Engine Ignition article. For ECT sensor tests, Refer to Electronic Engine Controls article. For EGR information, Refer to Engine Emission Control article. For fuel temperature sensor, IAT sensor and MAF sensor tests, Refer to Electronic Engine Controls article. For evaporative emissions components, Refer to Evaporative Emissions article. Check fuel pressure. For ignition system, Refer to Engine Ignition article. For ECT sensor tests, Refer to Electronic Engine Controls article. For EGR information, Refer to Engine Emission Control article.
Difficult to start after hot soak (vehicle standing after engine has reached operating temperature)	Injector leak Fuel temperature sensor IAT sensor MAF sensor Purge valve Fuel pump Ignition system Coolant temperature sensor EGR valve stuck open	Refer to Fuel Injector - Removal and Installation . For fuel temperature sensor, IAT sensor and MAF sensor tests, Refer to Electronic Engine Controls article. For evaporative emissions components, Refer to Evaporative Emissions article. Check fuel pressure. For ignition system, Refer to Engine Ignition article. For ECT sensor tests, Refer to Electronic Engine Controls article. For EGR information, Refer to Engine Emission Control article.
Engine stalls soon after start	Breather system disconnected/restricted ECM relay Harness MAF sensor Coolant temperature sensor Ignition system Air filter restricted Fuel lines Fuel pressure sensor Air leakage	For breather system, Refer to Engine Emission Control article. For ECM relay, MAF sensor and ECT sensor tests, Refer to Electronic Engine Controls article. For ignition system, Refer to Engine Ignition article. For air filter information, Refer to Intake Air Distribution and Filtering article. For fuel line information, Refer to Fuel Tank and Lines article. For fuel pressure sensor tests, Refer to Pinpoint Test B . For intake system information, Refer to Intake Air Distribution and Filtering article.
Engine hesitates/poor acceleration	Fuel pump Injector leak Fuel pressure Fuel lines Air leakage Throttle sensors Throttle motor Ignition system Exhaust gas recirculation Oxygen sensors Transmission malfunction Restricted pedal travel (carpet, etc) APP sensor	Check fuel pressure. For fuel pressure sensor tests, Refer to Pinpoint Test B . For fuel line information, Refer to Fuel Tank and Lines article. For intake system, Refer to Intake Air Distribution and Filtering article. For throttle position sensor and throttle motor tests, Refer to Electronic Engine Controls article. For ignition system, Refer to Engine Ignition article. For exhaust gas recirculation, Refer to Engine Emission Control article. Check for DTCs relating to Oxygen sensors. Refer to the DTC index for pinpoint tests for DTC set. For transmission information, Refer to Automatic Transmission/Transaxle article. Check accelerator pedal travel. For APP sensor tests, Refer to Electronic Engine Controls article.
Engine backfires	Fuel pump Fuel lines Air leakage MAF sensor Oxygen sensors Ignition system Sticking VCT hub APP sensor	Check fuel pressure. For fuel line information, Refer to Fuel Tank and Lines article. For intake system, Refer to Intake Air Distribution and Filtering article. For MAF sensor tests, Refer to Electronic Engine Controls article. Check for DTCs relating to Oxygen sensors. Refer to the DTC index for pinpoint tests for DTC set. For ignition system, Refer to Engine Ignition article. For VCT information, Refer to Engine article. For APP sensor tests, Refer to Electronic Engine Controls article.
Engine surges	Fuel pump Fuel lines MAF sensor Harness Throttle sensors Throttle motor Ignition system	Check fuel pressure. For fuel line information, Refer to Climate Control System - General Information article. For MAF sensor, throttle sensor, and throttle motor relay tests, Refer to Electronic Engine Controls article. For ignition system, Refer to Engine Ignition article.
Engine detonates/knocks	KS/circuit malfunction Fuel pump Fuel lines Fuel pressure sensor MAF sensor Oxygen sensors Air leakage Sticking VCT hub BARO sensor malfunction	For KS circuit tests, Refer to Electronic Engine Controls article. Check fuel pressure. For fuel line information, Refer to Fuel Tank and Lines article. For fuel pressure sensor tests, Refer to Pinpoint Test B . For MAF sensor and oxygen sensor tests, Refer to Electronic Engine Controls article. For intake system, Refer to Intake Air Distribution and Filtering article. Check DTCs for VCT range/performance fault. For VCT information, Refer to Engine article. For BARO sensor, contact Dealer technical support for advice on possible ECM failure
No throttle response	APP sensor malfunction Throttle sensors Throttle motor	For APP sensor, throttle position sensor and throttle motor relay tests, Refer to Electronic Engine Controls article.
Poor throttle response	APP sensor malfunction Throttle sensors Coolant temperature sensor MAF sensor Transmission malfunction Traction control event Air leakage Breather system disconnected/restricted	For APP sensor, throttle position sensor, ECT sensor and MAF sensor tests, Refer to Electronic Engine Controls article. For transmission information, Refer to Automatic Transmission/Transaxle article. For intake system, Refer to Intake Air Distribution and Filtering article. For breather system information, Refer to Engine Emission Control article.