Most Likely Culprits (Fuel Related):
* Fuel Pressure Regulator: A faulty fuel pressure regulator could be allowing too much fuel into the cylinders, leading to flooding. This is a common cause of wet plugs and a hard start/no-start condition. Testing fuel pressure is crucial here.
* Fuel Injectors: One or more injectors could be stuck open, constantly spraying fuel into the cylinders even when the engine isn't running or firing properly. This is less likely to affect all cylinders, but possible. A fuel pressure test might also indicate this.
* Clogged Fuel Filter: A severely clogged fuel filter restricts fuel flow, but it's less likely to cause *wet* plugs unless there's another issue compounding it (like a failing pressure regulator).
Less Likely, but Possible (Ignition/Other Related):
* Distributor Cap/Rotor (if applicable): While less likely on a fuel-injected V6 (many didn't have distributors), a faulty distributor cap or rotor can lead to misfires and poor combustion, but wouldn't typically result in *wet* plugs. Check for cracks or corrosion.
* Ignition Coil(s): Weak or failing ignition coils can result in weak or inconsistent spark, leading to incomplete combustion and possibly wet plugs. You'd likely notice misfiring or rough running if the problem were intermittent.
* Crankshaft Position Sensor (CKP sensor): A faulty CKP sensor prevents the engine from receiving the correct timing signal, leading to inconsistent or no firing. This is less likely to cause wet plugs alone, more likely rough running or no start at all.
* Mass Airflow Sensor (MAF sensor): A faulty MAF sensor provides incorrect air/fuel ratio data to the computer, potentially leading to flooding, but again, this isn't the most common cause of *wet* plugs.
Troubleshooting Steps:
1. Fuel Pressure Test: This is the most important first step. You'll need a fuel pressure gauge and the appropriate adapter for your fuel rail. Compare the reading to the factory specification for your engine. Low pressure points to a fuel pump, filter, or regulator problem. High pressure often indicates a regulator issue.
2. Check the Fuel Filter: Visually inspect the fuel filter. If it's visibly clogged or old, replace it.
3. Inspect the Fuel Injectors (Advanced): This involves more advanced diagnostics and might require a fuel injector test or a pressure test on each injector. This is best done by a mechanic unless you're experienced.
4. Check Ignition System (if fuel pressure is good): If fuel pressure is within spec, then look at the ignition components as listed above. A mechanic with diagnostic tools is often helpful for these checks.
Important Note: Wet plugs can damage the catalytic converter if left unchecked because of the unburnt fuel. Avoid starting the vehicle repeatedly until the problem is diagnosed and fixed.
Because wet plugs strongly suggest a fuel delivery problem, focusing on the fuel pressure regulator and fuel injectors should be your priorities. If you're not comfortable working with fuel systems, take it to a qualified mechanic.
