2005 Lincoln Navigator Repair and Maintenance
A guide to problems, costs, maintenance and repair for your 2005 Lincoln Navigator
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2005 Lincoln Navigator ProblemsSpark Plugs May be Difficult to Remove
Our technicians tell us the spark plugs in this engine can be very difficult to remove. Ford has issued a service bulletin (08-7-6) to address this issue, which includes a recommended procedure on how to remove the plugs. Failure to follow the recommended procedure can result in the one or more spark plugs breaking off in the cylinder head.
The recommend procedure is as follows. Using this procedure will greatly reduce the chance of breaking a spark plug.
1. Break the spark plugs loose when the engine is warm.
2. Turn each plug 1/8 to 1/4 turn and soak the treads with 1/2 to 3/4 teaspoon of Motorcraft Carburetor Tune-Up Cleaner or a quality penetrating oil. Do not try to remove the plugs at this time.
3. Let the threads soak for at least 15 minutes.
4. After the soak period, tighten and loosen each spark plug, working it back and forth until the turning effort is reduced. Then, you can remove the spark plug.
There are special tools available to remove the broken spark plugs and repair shops will often charge additional labor time, over and above the quoted spark plug replacement cost, for the removal of each broken spark plug.
In high dust areas, problems with the EGR system are common. The filter for the EGR solenoid may plug and cause the EGR to activate when it should not; this can cause the engine to stall. The dirty filter should be replaced to correct this concern.
Checking and adjusting the AC compressor clutch air gap can extend the service life of the AC compressor.
2005 Lincoln Navigator QuestionsWhy does my hydraulic pump malfunction when it's cold? (1 answer)
It works fine when it's warm outside.