For 1990-2009 cars

#### Excessive Exhaust Odors Symptom

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
Definition: The vehicle has an excessive rotten egg smell. (Excessive odors do not necessarily indicate excessive emissions.)
1 | Did you perform the On-Board Diagnostic (OBD) System Check? | -- | Go to Step 2 | Go to the Powertrain On Board Diagnostic (OBD) System Check
2 |

1. Perform a bulletin search.
2. If a bulletin that addresses the symptom is present, correct the condition as instructed in the bulletin.

Was a bulletin found that addresses the symptom?

--

Go to Step 17

Go to Step 3

3 | Did you perform a thorough visual/physical check? | -- | Go to Step 4 | Go to Symptoms for the Visual /Physical Check
4 |

1. Check for any vacuum leaks in the following areas:

• | The vacuum lines

• | The intake manifold

• | The throttle body

2. If a problem is present, repair as necessary.

Did you locate any vacuum leaks?

--

Go to Step 17

Go to Step 5

5 |

1. Check the fuel cap for a proper installation.
2. Secure the fuel cap if necessary.

Was the fuel cap installed properly?

--

Go to Step 6

Go to Step 17

6 |

1. Check the fuel pressure. Perform Fuel System Diagnosis .
2. If a problem is present, repair as necessary.

Was a problem found?

--

Go to Step17

Go to Step 7

7 |

1. Check for a malfunctioning, plugged, or incorrectly installed crankcase ventilation valve. Also, check the crankcase ventilation system for any plugging.
2. If a problem is present, repair as necessary.

Was a problem found?

--

Go to Step 17

Go to Step 8

8 |

1. Check the injector connections.
2. If any of the injector connectors are connected to an incorrect cylinder, correct as necessary.

Was a problem found?

--

Go to Step 17

Go to Step 9

9 |

1. Perform Fuel Injector Solenoid Coil Test .
2. If a problem is present, repair as necessary.

Was a problem found?

--

Go to Step 17

Go to Step 10

10 |

1. Refer to Engine Cooling for cooling system diagnosis.
2. If a problem is present, repair as necessary.

Was a problem found?

--

Go to Step 17

Go to Step 11

11 |

1. Check the EVAP canister for fuel loading.
2. If a problem is present, repair as necessary.

Was a problem found?

--

Go to Step 17

Go to Step 12

12 | Remove any excessive carbon buildup with a top engine cleaner. Refer to the instructions on top of the engine cleaner can. Is the exhaust odor still present? | -- | Go to Step 13 | Go to Step 17
13 | Check the items that can cause the engine to run rich. Make any of the necessary repairs. Is the exhaust odor still present? | -- | Go to Step 14 | Go to Step 17
14 | Check the items that can cause the engine to run lean. Make any necessary repairs. Is the exhaust odor still present? | -- | Go to Step 15 | Go to Step 17
15 |

1. Check for the following Engine Mechanical problems.Refer to Engine Mechanical:

• | Low compression

• | Sticking valves

• | A hydraulic valve lifter problem

• | Leaking cylinder head gaskets

• | A worn or incorrect camshaft

• | Incorrect cam timing

• | A damaged timing belt

2. If a problem is present, repair as necessary.

Was a problem found?

--

Go to Step 17

Go to Step 16

16 |

1. Review all of the diagnostic procedures within this table.
2. If you have completed all of the procedures and no malfunctions have been found, review/inspect the following:

• | The scan tool data

• | The Freeze Frame data

• | All of the electrical connections within a suspected circuit and/or system

3. If a problem is present, repair as necessary.

Was a problem found?

--

Go to Step 17

Go to Step 3

17 | Operate the vehicle under the same conditions (as closely as possible) as when the original symptom occurred. Is the original symptom still present? | -- | Go to Step 3 | The repair is complete. If another driveability symptom exists, refer to Symptoms .