* Distributor Cap and Rotor: These components are prone to cracking over time, and cracks can allow moisture to penetrate, leading to misfires and stalling. Wet conditions exacerbate this. Inspect for cracks, corrosion, or wear.
* Ignition Wires (Spark Plug Wires): Worn or damaged ignition wires can develop leaks in their insulation, allowing moisture to short-circuit the high voltage needed to fire the spark plugs. This is especially problematic in wet weather. Look for cracks, fraying, or signs of arcing.
* Spark Plugs: While less likely to be the *sole* cause in this scenario, wet conditions can exacerbate problems with worn or fouled spark plugs. They might be able to fire when dry, but fail when moisture interferes.
* Cranking Sensor/Crankshaft Position Sensor (CKP): Located on the engine block, this sensor provides crucial timing information to the ignition system. Moisture can cause a faulty reading, leading to erratic operation or stalling.
* Coil Pack (if equipped): A failing coil pack can cause misfires, and moisture can worsen this. Cracks or corrosion in the coil pack itself can contribute to the problem.
* Mass Airflow Sensor (MAF): While less directly related to ignition, a dirty or wet MAF sensor can provide incorrect air-fuel mixture data to the engine's computer, causing rough running and stalling. Wet conditions can contaminate the sensor's delicate element.
Troubleshooting Steps:
1. Visual Inspection: Start by thoroughly inspecting the distributor cap, rotor, ignition wires, and spark plugs for any signs of damage, corrosion, or moisture intrusion.
2. Check for Spark: Use a spark tester to check if each spark plug is receiving a strong and consistent spark.
3. Clean Connections: Clean all electrical connections related to the ignition system. Use a wire brush and contact cleaner to remove corrosion.
4. Replace Suspect Parts: If you find any damaged components, replace them immediately. It's often more cost-effective to replace a whole set of ignition wires than to replace individual faulty ones.
5. Professional Diagnosis: If the problem persists after a thorough inspection and replacement of suspect parts, take your Blazer to a qualified mechanic for a professional diagnosis. They have specialized tools to test components like the crankshaft position sensor and MAF sensor.
Remember, safety first! If your Blazer is stalling unexpectedly, avoid driving it in hazardous conditions until the issue is resolved.
