Diagnostic Procedure

Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, go to DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - 2.2L ION article.
Turn ignition switch to RUN position, engine OFF. Observe the DTC information using a scan tool. Does the scan tool display DTCs P0261, P0264, P0267, P0270, P0336, P0601, P0602, P0641, P1621, P1631 or P2533? If yes, diagnose affected DTC(s). See DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - 2.2L ION article. If no, go to next step.
Does the scan tool display any Body Control Module (BCM) Vehicle Theft Deterrent (VTD) DTCs? If yes, diagnose affected DTC(s). See appropriate BODY CONTROL MODULES article in ACCESSORIES & EQUIPMENT. If no, go to next step.
Monitor the ignition 1 signal parameter using a scan tool. Is the ignition 1 signal parameter at battery voltage? If yes, go to next step. If no, go to step 11 .
Attempt to start the engine. Using a scan tool, monitor the CMP resync counter parameter while the engine is cranking. Does the CMP resync counter increment while cranking the engine? If yes, go to next step. If no, go to ELECTRONIC IGNITION SYSTEM DIAGNOSIS under IGNITION SYSTEMS.
Command the fuel pump relay ON using a scan tool. Does the fuel pump operate? If yes, go to next step. If no, go to FUEL PUMP ELECTRICAL CIRCUIT DIAGNOSIS under FUEL SYSTEMS.
Turn ignition switch to OFF position. Remove the fuel pump relay. Remove the ignition coil housing. Not grounding the ignition coil housing, may cause erratic spark. Install a jumper wire with clips on both ends from the top of the ignition coil housing to ground. Install Ignition Test Wires (J 36012-A, J 43883). Install Spark Tester (J 26792, SA9199Z) on the No. 1 spark plug jumper wire. Connect the No. 4 (companion to No. 1) spark plug jumper wire to ground. Crank the engine with the remaining spark plug jumper wires connected. Repeat procedure by installing the spark tester on the No. 4 jumper and grounding the No. 1 jumper. Do the same for No. 2 and No. 3 spark plugs. Ensure the companion wire is grounded. Does the spark tester spark on all cylinders? If yes, go to next step. If no, go to ELECTRONIC IGNITION SYSTEM DIAGNOSIS under IGNITION SYSTEMS.
Turn ignition switch to OFF position. Disconnect a fuel injector harness connector. Install Injector Test/Noid Light (J 34730-405) to the fuel injector connector. Attempt to start the engine. Does the test light blink while the engine is cranking? If yes, go to next step. If no, go to FUEL INJECTOR CIRCUIT DIAGNOSIS under FUEL SYSTEMS in SYSTEM & COMPONENT TESTING - 2.2L ION article.
Turn ignition switch to OFF position. Install Gauge Bar Set (SA9127E), or equivalent. Turn ignition switch to RUN position, engine OFF. Command the fuel pump relay ON using a scan tool. Is the fuel pressure 50-60 psi (345-414 kPa) while the fuel pump is operating? If yes, go to next step. If no, go to FUEL SYSTEM DIAGNOSIS under FUEL SYSTEMS.
Inspect for the following conditions:
- A collapsed air intake duct.
- A restricted air filter element.
- Gas or coolant fouled spark plugs. If the spark plugs are fouled, determine what caused the condition.
- Any engine mechanical conditions, worn timing chain and gears, or low compression. See appropriate article in ENGINES.
- A restricted exhaust system. See RESTRICTED EXHAUST under SYMPTOMS in TROUBLE SHOOTING - NO CODES - 2.2L ION article.
- An inaccurate Engine Coolant Temperature (ECT) sensor. See DTC P0117: ENGINE COOLANT TEMPERATURE SENSOR - LOW VOLTAGE or DTC P0118: ENGINE COOLANT TEMPERATURE SENSOR - HIGH VOLTAGE under DIAGNOSTIC TESTS in SELF-DIAGNOSTICS - 2.2L ION article.
- An inaccurate Manifold Absolute Pressure (MAP) sensor or Throttle Position (TP) sensor. See DTC P0106: MANIFOLD ABSOLUTE PRESSURE SYSTEM PERFORMANCE , DTC P0122: TP SENSOR CIRCUIT - LOW VOLTAGE and DTC P0123: TP SENSOR CIRCUIT - HIGH VOLTAGE under DIAGNOSTIC TESTS in SELF-DIAGNOSTICS - 2.2L ION article.
After completing the inspections/repairs, go to step 14 .
Test the ignition 1 voltage circuits that are supplied by the ECM fuse for an open or for a short to ground. Replace the fuse, if necessary. Did you find and correct the condition? If yes, go to step 14 . If no, go to next step.
Inspect for poor connections at the ECM harness connector. Did you find and correct the condition? If yes, go to step 14 . If no, go to next step.
Replace the ECM. Perform ECM relearn procedure. See ENGINE CONTROL MODULE REPROGRAMMING under PROGRAMMING in SELF-DIAGNOSTICS - 2.2L ION article. After repair, go to next step.
Clear the DTCs using a scan tool. Turn ignition switch to OFF position for 30 seconds. Attempt to start the engine. Does the engine start then continue to run? If yes, go to next step. If no, go to step 2 .
Allow the engine to reach operating temperature. Observe the DTC information using a scan tool. Are there any DTCs that have not been diagnosed? If yes, go to DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - 2.2L ION article. If no, system is okay at this time.