Possible Causes & Corrections

WARNING: This page is about a different car, the 2003 Pontiac Aztek and 2003 Buick Rendezvous. However, it is still accessible from the selected car via links, so may be relevant.

Check for the following items:

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Be sure driver understands transmission Torque Converter Clutch (TCC) and A/C compressor operation, as explained in the owner's manual. Inform customer how TCC and A/C clutch operates.
Monitor the Heated Oxygen Sensors (HO2S). See DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - 3.4L AZTEK & RENDEZVOUS article. The HO2S should respond quickly to different throttle positions. If not, inspect the HO2S for Silicone or other contaminants from fuel or use of improper RTV sealant. The sensors may have a White powdery coating. Silicone contamination causes a high but false HO2S signal voltage which is a rich exhaust indication. The PCM will reduce the amount of fuel delivered to the engine, causing a severe driveability problem.
Inspect the Mass Airflow (MAF) sensor and related wiring. See DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - 3.4L AZTEK & RENDEZVOUS article.
Inspect the air intake ducts for being collapsed, damaged areas, looseness, improper installation, or leaking especially between the MAF sensor and throttle body.
Monitor the 24X crank sensor and the CMP sensor signal present parameters on the scan tool. See DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - 3.4L AZTEK & RENDEZVOUS article. If both sensors are not responding, test each sensor feed circuit. Each sensor uses a separate supply circuit but are internally connected to power. Test all CKP sensor "A" and CMP sensor circuits for intermittents.
Monitor the 3X crank sensor parameter on the scan tool. See DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - 3.4L AZTEK & RENDEZVOUS article. If the 3X crank sensor parameter is not responding, inspect the CKP sensor "B" and related circuits for intermittents. Inspect the Ignition Control (IC) circuit, IC timing control circuit, low resolution engine speed signal circuit and the low reference circuit for intermittents. If these circuits become open or shorted may not set a DTC immediately, but are capable of causing driveability complaints.
Test the CKP sensor "B" for an internal short. See DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - 3.4L AZTEK & RENDEZVOUS article.
Test the EGR system for proper operation. See DIAGNOSTIC TROUBLE CODE DEFINITIONS in SELF-DIAGNOSTICS - 3.4L AZTEK & RENDEZVOUS article.
Test the fuel pressure. Refer to FUEL SYSTEMS in BASIC DIAGNOSTIC PROCEDURES - 3.4L AZTEK & RENDEZVOUS article.
Inspect for contaminated fuel.
Ensure each fuel injector harness is connected to the correct fuel injector/cylinder.
Inspect any items which may cause an engine to run rich. Using scan tool, long term fuel trim is significantly in the negative range.
Inspect any items that may cause an engine to run lean. Using scan tool, long term fuel trim is significantly in the positive range.
Inspect for proper ignition voltage output using Spark Tester (J-26792).
Test the TCC operation.
Inspect the exhaust system for possible restriction. Inspect exhaust system for damaged or collapsed pipes. Inspect muffler for heat distress or possible internal failure. Test for possible plugged catalytic converter by testing the exhaust system backpressure.