Excessive Exhaust Emissions

If vehicle fails emission test or has excessive "rotten egg smell", check the following items:

• Check fuel pressure.
• Check for leaking fuel injector if vehicle is running rich.
• Check canister purge and PCV valve operation.
• Check throttle position sensor or switch if vehicle is running rich.
• Check Manifold Absolute Sensor (MAP) if vehicle is running rich.
• Check EGR operation.
• Check for vacuum leaks.
• Ensure ignition timing and controls are working properly.
• Check for faulty spark plugs or spark plug wires.
• Check for exhaust leaks.
• Ensure engine warms to normal operating temperature.
• Ensure correct ECM application. Check with dealer for latest application information.
• Check for lead contaminated catalytic converter (look for removal of fuel filler neck restrictor).
• Check for defective oxygen sensor.