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A. Penland
A. Penland, Ford Senior Master Technician, ASE
Category: Lincoln
Satisfied Customers: 6603
Experience:  ASE Master Certified. ASE Gasoline Engine Performance Certified,Ford Senior Master Technician
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Lincoln navagator: 2004 lincoln navagator 104k rough idle and

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2004 lincoln navagator 104k rough idle and miss at 30-40 mph. changed plugs and 4 (expensive) coils. no better. Is there a recall on the heads and all the problems?
I am old school and would rather have a 427 tunnel port side oiler than this crap!

Hello and thanks for using Just Answer.I will try my best to help you with your question.


Have you checked for any codes in the PCM (Engine Computer)?

What four coils did you replace?

What side and cylinder numbers?

Customer: replied 4 years ago.

1. yes

2. 1-3-7-8

had to remove and disconnect the computer on the passenger side to get to the plugs. After re installing, pluged a computer codes present.

Is there any recalls on this motor?

No recalls on the engine. I am a little confused on the coils you replaced. Fords engines are number 1-2-3-4 starting at the fan belt on the passenger side and then 5-6-7-8 on the drivers side starting at the fan belt.

What told you to replace coils 1-3-7-8?

Customer: replied 4 years ago.

yes....1&3.....pass side....7&8 driver side. They came apart upon removal

and that is all the had in Clearlake.

This didn't stop the rough idel or at speed.

A warrenty says to remove the head....10 $75.00 an hour!

Did a repair shop tell you the cylinder head needs to be removed?
Did they get any codes from the PCM (Engine Computer)?
Customer: replied 4 years ago.

No....searching for possible problems.....bad valve?

No codes from the comp.

Your problem is either caused by a bad spark plug, bad ignition coil or a bad injector. But I would have the system properly tested before replacing any more parts. You need to isolate what cylinder is causing the miss fire/rough idle and then isolate what is causing the miss fire in that cylinder.


Customer: replied 4 years ago.

The hook up to the computer says no problems ....this really sucks.

Bring back pluge,points, condencer cap rotor

I am on your side completely!

I work on Fords everyday and they are getting more and more complex. You almost have to be a computer genius to repair and/or diagnose them any more. They are now full of computers and modules.

Customer: replied 4 years ago.

so true,

now I find that the comp says #2&#7 have the problem and the "power balance" is uping the fule to the others.....CRAP!

Swap the coils to the next cylinder and clear all codes. Then retest and see if the cylinders change to the ones the coils got moved to. Do the same to the spark plugs and then the fuel injectors.

Move the coils then retest. Then move the spark plugs and retest, then move the fuel injectors. Do not move them all at once though.


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