I have a 2000 Grand Marquise 4.6. It runs well when cold, once warmed up it runs rough.

30

Asked by Jan 07, 2017 at 05:55 PM about the 2000 Mercury Grand Marquis LS

Question type: Maintenance & Repair

I had changed the plugs hoping this would solve the problem, it did not, though the plugs were in sad shape.  The only error code I am receiving is a misfire in #2 cylinder.  I listened to the injector it sounds consistent with the others.  Should my next step be to replace the coil pack over that one spark plug?  I've never experienced a coil acting this way.  I realize some things are a process of elimination, but I don't want to just throw parts into it.

7 Answers

87,155

P0302 MERCURY - Cylinder 2 Misfire Detected.... Possible causes - Faulty spark plug 2 - Clogged or faulty fuel injector 2 - Faulty ignition coil 2 - Fuel injector 2 harness is open or shorted - Fuel injector 2 circuit poor electrical connection - Ignition coil 2 harness is open or shorted - Ignition coil 2 circuit poor electrical connection - Insufficient cylinder 2 compression - Incorrect fuel pressure - Intake air leak

2 people found this helpful.
30

Thank you for your insights. I will press in this direction. You have been a big help. Thanks again

1 people found this helpful.
30

So, In my situation, I replace the coil for the #2 cylinder. I cleared the code, took it for a test drive and drove with the live data stream hooked up so I could make sure the engine has reached it normal temp range. It ran great....smooth all the way around. Thanks again Rowefast.

1 people found this helpful.
67,875

You should have replaced all coils with Motorcraft coils. You likely will have problems again as this is a common issue with these cars. Using aftermarket coils is a hit or miss proposition. Sometimes they work and sometimes they don't last very long.

2 people found this helpful.
87,155

Your most welcome puzzled2...

30

Thank you Bob, I agree with your comment about replacing all the coils. I don't like doing things over. We have had a lot of repairs the last couple of months and our car funds were depleted. I did buy a Motorcraft coil though. Thanks again for your thoughts.

1 people found this helpful.
67,875

Good, Motorcraft although expensive is the best part for this application. Best of luck with it.

Your Answer:

Grand Marquis

Looking for a Used Grand Marquis in your area?

CarGurus has 8 nationwide Grand Marquis listings and the tools to find you a great deal.

Postal Code:

Mercury Grand Marquis Experts

  • #1
    Tracy Hooks
    Reputation
    6,100
  • #2
    kbro
    Reputation
    2,260
  • #3
    Js08016
    Reputation
    2,180
View All

Related Models For Sale

Used Lincoln Town Car
10 listings starting at $6,495
Used Ford Crown Victoria
21 listings starting at $4,986
Used Chevrolet Impala
23 Great Deals out of 868 listings starting at $2,894
Used Chevrolet Tahoe
10 Great Deals out of 784 listings starting at $5,900
Used Ford Taurus
16 Great Deals out of 377 listings starting at $3,900
Used Honda Accord
38 Great Deals out of 1,652 listings starting at $3,490
Used Ford Mustang
45 Great Deals out of 1,253 listings starting at $4,685
Used Ford F-150
134 Great Deals out of 11,446 listings starting at $1,995
Used Toyota Camry
36 Great Deals out of 2,122 listings starting at $2,450
Used Chevrolet Silverado 1500
102 Great Deals out of 11,132 listings starting at $4,950

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use.