How To Test The Ignition COP Coils (2001-2007 3.0L V6 Ford Escape)

Testing the COP coils in your 3.0L V6 Ford Escape (or Mazda Tribute) can be a challenge, since three of them are under the intake manifold plenum (this tutorial can be applied to several other 3.0 V6 Ford models).

The three that are underneath the intake plenum are the COP coils for cylinders #1, #2 and #3 (cylinder #1 is the one closest to the serpentine belt).

These three can not be easily tested like the ones that are on the engine bank that is closest to the radiator.

Well, in this article, I'm gonna' offer you a comprehensive testing strategy that'll help you get to the bottom of the misfire on your 3.0L V6 Ford Escape or 3.0L V6 Mazda Tribute.

You can find this tutorial in Spanish here: Cómo Probar Las Bobinas De Encendido (3.0L Ford Escape) (at: autotecnico-online.com).

APPLIES TO: This tutorial applies to the following vehicles:

• 3.0L V6 Ford Escape: 2001, 2002, 2003, 2004, 2005, 2006, 2007.
• 3.0L V6 Mercury Mariner: 2005, 2006.
• 3.0L V6 Mazda Tribute: 2001, 2002, 2003, 2004, 2005, 2006.

Important Tips And Suggestions

TIP 1: Although the main focus of this article is testing the COP coils on a 3.0L Ford Escape (3.0L Mazda Tribute), the tests apply to the vehicles listed in the 'Applies To' box on the second column (since these vehicles also have the COP coils for cylinders #1, #2, and #3 underneath a plastic intake manifold plenum).

TIP 2: The fuel pump relay needs to be removed before testing the COP coils for spark. This is a safety precaution that will prevent the engine from starting.

The photo of the fuel pump relay (in the fuse box) in this article is of a Ford Escape (Mazda Tribute). You can see this photo here: Location Of The Fuel Pump Relay. If your vehicle is not a Ford Escape, you'll need to consult your owner's manual or a repair manual for the location of the fuel pump relay on your specific vehicle.

TIP 3: Testing the COP coils on your Ford Escape may require removing the top part of the intake manifold (known as the intake manifold plenum).

TIP 4: When removing the plastic intake manifold plenum, you've got to be extra careful nothing falls into the open intake manifold ports.

Once the plenum is off the intake manifold, stuff clean rags into the 6 open ports to prevent any foreign object (like a bolt) from falling inside.

Symptoms Of A Bad Ford Escape COP Coil

The most common symptom of a bad COP ignition coil on your Ford Escape is a misfire condition. What 'throws a wrench into the works', is that the misfire condition sometimes doesn't set a diagnostic trouble code (DTC).

You may also see one or more of the following symptoms:

1. Check engine light is on with one or several of the following DTCs :
   • P0300: Random Cylinder Misfire.
   • P0301: Cylinder #1 Misfire.
   • P0302: Cylinder #2 Misfire.
   • P0303: Cylinder #3 Misfire.
   • P0304: Cylinder #4 Misfire.
   • P0305: Cylinder #5 Misfire.
   • P0306: Cylinder #6 Misfire.
2. Rough idle.
3. Bad gas mileage.
4. Excessive tail-pipe emissions (pollution).
5. A "rotten egg" smell coming from the tailpipe.
   • This smell is caused by unburned gasoline from the misfiring cylinder overloading the catalytic converter's oxidation process.
6. Engine misfires under load. In other words; the engine starts to miss as you give it gas.

What Tools Do I Need To Test The Ford Escape COP Coils?

You'll test and diagnose the ignition coils on the car or truck with some very basic tools. You'll need:

1. A 12 Volt automotive test light.
2. A multimeter.
3. An HEI spark tester.
   • This inexpensive spark tester is a MUST have tool to be able to correctly diagnose the ignition coil pack on your Ford (or Mercury or Mazda) vehicle with the info/tests in this article (don't have an HEI spark tester? Need to buy one? You can buy it here: OTC 6589 Electronic Ignition Spark Tester).
4. You'll need a helper to help you crank the engine while you perform the tests.
5. A repair manual.
   • For any remove and replace info that I don't cover in this article.

A scan tool will come in handy to read any misfire diagnostic trouble codes stored in your Ford Escape's PCM's memory but to test the actual COP coils -You DO NOT need a scan tool.

What Causes My Ford Escape To Misfire?

Over the years, I've identified 3 major issues that are usually the root cause of a misfire condition on a 3.0L Ford Escape (Mazda Tribute) and more than likely your Ford Escape (Mazda Tribute) is experiencing one of them. They are:

1. A bad ignition coil.
   • The coil just stops sparking due to age.
   • A bad COP coil will definitely set a misfire diagnostic trouble code.
   • This is usually the easiest issue to diagnose and resolve.
2. Oil leaking into the spark plug tubes from the valve cover gaskets.
   • The COP coil and spark plugs are centered in the middle of the valve cover gasket and the valve cover gasket is the one tasked with keeping oil from leaking into the spark plug tubes.
3. Intake manifold gasket leaking vacuum.
   • This usually causes a P0300 random misfire code.
   • Ford, in its infinite wisdom, decided to use plastic and rubber gaskets for the intake manifold and the intake manifold plenum on your Ford Escape (Mazda Tribute).
   • Over time, these harden and become compressed to the point that they stop sealing.
   • When this happens, you'll experience a rough idle condition at engine start up, but once the engine warms up (and the gaskets warm up, loosen up and expand), the problem goes away.

Where To Buy The Ignition Coils And Save

Whenever you're ready to replace the ignition coils on your 3.0L V6 Ford Escape or Mazda Tribute, I want to recommend the following two automotive brands, Standard Motor Products and Delphi. Both are brands I have used for years and never hesitate to recommend:

START HERE: Checking For Cylinder Misfire Codes

Before diving in and pulling ignition coils, first see if the PCM has set any misfire codes. Hook up your code reader or scan tool and check for stored DTCs.

• If you have a misfire code (P0301–P0306):

  Use the cylinder ID image (above) to match the code to the misfiring cylinder. This also tells you if the cylinder is in the front bank (easy access) or under the intake manifold plenum.

  • P0301, P0302, P0303 —Cylinders under the plenum.
  • P0304, P0305, P0306 —Cylinders in the front bank (not under the plenum).

  If the trouble code indicates the misfiring cylinder is under the plenum, go to TEST 1: Bank 1 COP Coil Tests -Under Plenum (No Misfire Codes).

  If misfiring cylinder is up front (not under the plenum), go to TEST 2: Bank 2 COP Coil Tests (With Misfire Codes).

• If you don't have a misfire code, or only P0300 (Random Misfire):

  Do some exploratory checks before removing the plenum. Start by testing the three front ignition coils (cylinders #4, #5, and #6) with a spark tester. This clears them as suspects right away and lets you see if engine oil is leaking into the spark plug tubes (common with a failing valve cover gasket). If the front cover is leaking, the rear likely is too.

  Go to: TEST 3: Bank 2 COP Coil Tests (No Misfire Codes).

At this point, you'll know whether you can zero in on a specific coil or if you need to dig deeper into the rear bank.

TEST 1: Bank 1 COP Coil Tests -Under Plenum (No Misfire Codes)

If you're reading this, then you've got a specific Bank 1 cylinder misfire code (P0301, P0302, or P0303). Each one points to a misfire in a cylinder that's underneath the plastic intake manifold plenum.

In this section, you're gonna do two things to track down the root cause of the misfire:

• Test the COP coil (for the misfiring cylinder) with a spark tester.
• Check that the COP coil's spark plug boot and the spark plug aren't covered in engine oil (from a leaking valve cover gasket).

To get to the COP coil under the plenum, you'll have to remove it. Once it's out, and as a safety precaution, you'll test the accused COP coil by connecting it to a COP coil connector from the front bank of the engine (I'll explain this step in detail below).

IMPORTANT: Remove the fuel pump relay before you start testing for spark. This will prevent your Ford Escape (or Mazda Tribute) from starting. To see the location of the fuel pump relay, check out the photo here: Location Of The Fuel Pump Relay.

NOTE: Since you'll be removing the intake manifold plenum, there are certain precautions you need to take. For more info, see this section: Important Recommendations (COP Coils Under Plenum).

OK, this is what you'll need to do:

1. 1

   Remove the plastic intake manifold plenum.
   
   IMPORTANT: Once the plenum is off, stuff clean shop towels into the open intake manifold ports. This is a safety precaution to keep anything from falling into the ports (see photo number 2 of 5).

2. 2

   Disconnect and remove the COP coil that the misfire code points to as the misfiring one.

3. 3

   Remove the shop towels from the intake manifold ports, then re-install the plenum and bolt it back in place (it's OK to reuse the same old gasket at this point).
   
   I don't want to jump too far ahead, but in a few moments you're gonna crank the engine. Re-installing the plenum here is simply a safety precaution.

4. 4

   Disconnect one of the COP coils (in the front engine bank) from its electrical connector.
   
   NOTE: No need to remove this ignition coil —all you need to do is disconnect it from its 2-wire connector.

5. 5

   Connect the COP coil you removed from the rear bank to the electrical connector of the front-bank ignition coil you just disconnected.

6. 6

   Attach the spark tester to the COP coil and Ground the spark tester with a jumper cable to the battery negative (–) terminal.

7. 7

   Have your helper crank the engine while you watch the spark tester.

8. 8

   The spark tester will do one of two things: Spark or not spark.

Alright, there are 4 possible test results to choose from below, let's take a look at what your test results mean:

CASE 1: The COP coil DID NOT spark and was NOT covered in oil. This tells you that the COP coil is bad and needs to be replaced to solve the misfire condition.

CASE 2: The COP coil DID NOT spark and WAS covered in oil. This tells you that the COP coil is bad and needs to be replaced to solve the misfire condition and that you'll need to replace the valve cover gaskets.

There are some very specific recommendations to help you complete the repair head-ache free and you can find them here: Spark Plugs And Boots Soaked In Oil.

CASE 3: The COP coil sparked and was NOT covered in oil. This tells you that the COP coils is OK and not the cause of the misfire.

Since you still have a misfire, I suggest testing the following:

• Fuel injectors.
• Engine compression.

Although it's beyond the scope of this article to test the above, you have at least eliminated the COP coil as the source of the misfire condition.

CASE 4: The COP coil sparked and WAS covered in oil. This tells you that the misfire condition could be caused by the oil.

Since the COP coil boot was soaked with engine oil this means the spark plugs are swimming in oil too. To effectively solve the misfire issue on your Ford vehicle, there are some important recommendations you should take a look at here: Spark Plugs And Boots Soaked In Oil.

TEST 2: Bank 2 COP Coil Tests (With Misfire Codes)

If you're starting your ignition coil tests in this section, then you already have a specific misfire code (P0304, P0305, or P0306). Each of these codes points to a misfire in Bank 2 —and the coils for this bank aren't under the plenum.

Your mission here is to find out if your 3.0L V6 Ford Escape (or Mazda Tribute) is misfiring because of one of two things:

• A bad COP coil that's no longer sparking.
• Or engine oil leaking onto the COP coil's spark plug boot and spark plug (from a leaking valve cover gasket).

IMPORTANT: Remove the fuel pump relay before you start testing for spark. This will prevent your Ford Escape (or Mazda Tribute) from starting. To see the location of the fuel pump relay on the Ford Escape/Mazda Tribute, check out the photo here: Location Of The Fuel Pump Relay.

OK, this is what you'll need to do:

1. 1

   Disconnect and remove the COP coil that the misfire code indicates as the one that's misfiring.
   
   NOTE: Check to see if the COP coil's spark plug boot and the spark plug are covered in engine oil (from a leaking valve cover gasket).

2. 2

   Attach the spark tester to the COP coil.

3. 3

   Ground the spark tester using a jump start cable to the battery negative (-) terminal.

4. 4

   Have your helper crank the engine while you observe the spark tester.

5. 5

   The spark tester will do one of two things: Spark or NOT spark.

Alright, choose the CASE that best fits your spark test results:

CASE 1: The COP coil DID NOT spark and was NOT covered in oil. This tells you that the COP coil is bad and needs to be replaced to solve the misfire condition.

There are some very specific recommendations to help you complete the repair head-ache free and you can find them here: Important Recommendations (COP Coils Under Plenum).

CASE 2: The COP coil DID NOT spark and WAS covered in oil. This tells you that the COP coil is bad and needs to be replaced to solve the misfire condition and that you'll need to replace the valve cover gaskets.

There are some very specific recommendations to help you complete the repair head-ache free and you can find them here: Spark Plugs And Boots Soaked In Oil.

CASE 3: The COP coil sparked and was NOT covered in oil. This tells you that the COP coil is OK and not the cause of the misfire.

CASE 4: The COP coil sparked and WAS covered in oil. This tells you that the misfire condition could be caused by the oil.

Since the COP coil boot was soaked with engine oil this means the spark plugs are swimming in oil too. To effectively solve the misfire issue on your Ford vehicle, there are some important recommendations you should take a look at here: Spark Plugs And Boots Soaked In Oil.