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Diagnostic Procedures

WARNING: This page is about a different car, the 2002 Oldsmobile Aurora. However, it is still accessible from the selected car via links, so may be relevant.
  1. 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.
  2. Is there any MAP DTCs set? If yes, repair DTCs as necessary. See DIAGNOSTIC TROUBLE CODE DEFINITIONS . If no, go to next step.
  3. Check exhaust system for leaks and modification of original parts. If any problems are found, repair as necessary. Did you find and correct the condition? If yes, go to step  7. If no, go to next step.
  4. Check EGR valve gasket and pipes for leaks. If any problems are found, repair EGR system as necessary. Did you find and correct the condition? If yes, go to step  7. If no, go to next step.
  5. Remove EGR valve. Check EGR valve pintle and passages for leaks and/or restrictions. Did you find and correct the condition? If yes, go to step  7. If no, go to next step.
  6. Remove EGR inlet and outlet pipes from intake and exhaust manifolds. Inspect manifold EGR ports, inlet pipes and outlet pipes for blockage/damage. Did you find and correct the condition? If yes, go to next step. If no, see DIAGNOSTIC AIDS .
  7. Use the scan tool in order to clear the DTCs. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step  2.
  8. With a scan tool, observe the stored information, Capture Info. Does the scan tool display any DTCs that you have not diagnosed? If yes, see DIAGNOSTIC TROUBLE CODE DEFINITIONS . If no, system is okay.
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