WARNING: This page is about a different car, the 2004 Mercury Monterey and 2004 Ford Freestar. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: This section contains information, steps and procedures that may not be specific to your engine.
This section covers general procedures and diagnosis and testing of the engine system, except for exhaust emission control devices, which are covered in INTRODUCTION - CNG, FLEX-FUEL & GASOLINE .
The engine incorporates the following features:

a closed positive crankcase ventilation (PCV) system. For additional information, Refer to ENGINE - 3.9L & 4.2L .
an exhaust emission control system. For additional information, Refer to ENGINE - 3.9L & 4.2L .
an evaporative emission control system. For additional information, Refer to FUEL SYSTEM .

Some engines incorporate a fail-safe cooling system. Refer to ENGINE COOLING .

The engine, fuel system, ignition system, emissions system and exhaust system all affect exhaust emission levels and must be maintained according to the maintenance schedule. Refer to the scheduled Maintenance Guide.

Correct engine identification is required to order parts. Refer to IDENTIFICATION CODES .

For complete vehicle and engine identification codes, Refer to IDENTIFICATION CODES .

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.

• Brakes feel soft, pull hard to one side, or make grinding noises.

• The engine overheats, stalls repeatedly, or misfires under load.

• You are missing required tools, torque specs, or safe lifting equipment.

• You are not confident in the next step or safety outcome.

Safety Warning

Description And Operation: Engine

Use the Manual With the Right Hardware

When to See a Mechanic

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