TEST 3: Bank 2 COP Coil Tests (No Misfire Codes)
Since you don't have any specific cylinder misfire codes, in this test section, you'll test the 3 COP coils that are in the front of the engine. These are the coil-on-plug (COP) coils for cylinders #4, #5, and #6.
The purpose of testing these three COP coils first, is to make sure that they're sparking and that there isn't oil leaking down on the spark plugs.
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, to get your misfire troubleshooting going, this is what you need to do:
- 1
Remove cylinder #4's COP coil.
Once the COP coil is off, check to see if the COP coil's spark plug boot is covered and/or dripping with engine oil? - 2
Attach your spark tester to the COP coil (as shown in illustration above).
- 3
Ground the spark tester directly on the battery negative (-) terminal with a battery jump start cable.
- 4
Have your helper crank the engine.
- 5
You'll see one of two spark test results: Spark or no spark.
- 6
Disconnect the spark tester and re-install the ignition coil.
- 7
Repeat the spark test on the other COP coils (for cylinders #5 and #6).
Let's take a look at what your test results mean:
CASE 1: All 3 COP coils sparked and were NOT covered in oil. So far so good, since this means that the misfire doesn't live in these three cylinders.
This also means that you'll now need to test Bank 1 cylinders #1, #2, and #3 (which are underneath the plenum) for spark. Go to: TEST 4: Bank 1 COP Coil Tests -Under Plenum (No Misfire Codes).
CASE 2: All 3 COP coils sparked and WERE 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.
CASE 3: One of the COP coils DID NOT spark and none were covered in oil. The COP coil that did not spark is bad and must be replaced.
Since none of the COP coils were covered in engine oil, then it's pretty safe to assume that the ones in the back of the engine are not either. You'll need to replace the COP coil and road test to see if the problem is solved.
CASE 4: One of the COP coils DID NOT spark and was covered in oil. The COP coil that did not spark is bad and must be replaced.
You can make sure by plugging a good COP coil into the bad Cop coil's connector and checking for spark one more time. If the good COP coil sparks, then you now know beyond a shadow of a doubt that the PCM is activating the bad COP coil, but since it's fried, it's not sparking.
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 4: Bank 1 COP Coil Tests -Under Plenum (No Misfire Codes)
So far, you have verified that the COP coils for Bank 2 cylinders #4, #5, and #6 are sparking and that they're not covered in engine oil.
The next step (and the purpose of this test) is to see if one of the COP coils (that are underneath the plenum) is bad and not sparking and thus the cause of your misfire condition.
You'll also be able to see if the COP coil boots are covered in engine oil or not. Remember, these are the COP coils for Bank 1 cylinders #1, #2, and #3.
In a nutshell, what you're gonna' do is to place these COP coils in front and spark test them to see if they are sparking or not.
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.
Let's get started:
- 1
Disconnect and remove the 3 ignition coils (COP coils) for cylinders #4, #5, and #6. Then remove the plastic intake manifold plenum.
IMPORTANT: As soon as the plenum is off, stuff clean rags into the open intake manifold ports. This keeps anything from accidentally falling inside. - 2
Disconnect and remove the 3 ignition coils for cylinders #1, #2, and #3 (these sit under the plenum).
NOTE: Before pulling them out, label each coil with its cylinder number. This will be super important later, when it comes time to pinpoint the misfiring cylinder. - 3
Remove the rags from the intake ports and reinstall the plenum. Go ahead and bolt it down —it's fine to reuse the same gaskets for this test.
We're going to crank the engine in a later step, and reinstalling the plenum now is simply a safety precaution. - 4
Take 2 of the ignition coils you just removed from the rear bank and install them in the front bank (where cylinders #4, #5, and #6 are located). Bolt them down and connect them to the front-bank electrical connectors.
In case you're wondering, it doesn't matter which front-bank cylinder you drop them into for this test. - 5
Connect your spark tester to the 3rd ignition coil and connect it to the remaining front-bank electrical connector.
- 6
Ground the spark tester directly to the battery's negative (-) terminal with a battery jump start cable.
- 7
Have your helper crank the engine while you watch the spark tester.
- 8
You'll see one of two things: The spark tester will either spark or it won't.
- 9
Disconnect the spark tester and reinstall that coil onto the valve cover.
- 10
Repeat the spark test with the other 2 coils and note if they're sparking or not.
Let's take a look at what your test results mean:
CASE 1: All 3 COP coils sparked and were NOT covered in oil. This tells you that the 3 COP coils are OK and not the cause of the misfire.
OK, so far you have tested all 6 COP coils with a dedicated spark tester (and therefore you can trust your test results) and you have NO oil leaking onto the spark plug boots or spark plugs, this means that the most likely thing that's causing your misfire condition is the intake manifold gasket and the plenum gasket.
You should at this point also plan on replacing the spark plugs with original Motorcraft spark plugs, I don't recommend that you use anything but.
CASE 2: All 3 COP coils sparked and WERE 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.
CASE 3: One of the COP coils DID NOT spark and none were covered in oil. The COP coil that did not spark is bad and must be replaced.
CASE 4: One of the COP coils DID NOT spark and was covered in oil. The COP coil that did not spark is bad and must be replaced.
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.
Important Recommendations (COP Coils Under Plenum)
In you found a bad coil-on-plug (COP) coil that feeds spark to one of the cylinders in the rear engine bank (and thus underneath the intake manifold plenum), in this section I want to offer you some specific recommendations so that you can finish the job and not have any comebacks:
- Remove and check the spark plugs for wear and tear.
- If you have never replaced the spark plugs and the engine has over 100,000 miles, replace them all. No 'ifs, ands, or buts' on this point.
- Use only the Motorcraft® brand of spark plugs. Motorcraft is the factory original spark plug that will work head-ache free in your Ford vehicle.
- Using any other 'high performance' spark plug is not only a waste of money, but may cause a rough idle or misfire condition.
- Replace the plenum gasket with a new one.
- Avoid the temptation to use RTV Silicone gasket sealer to aid the rubber plenum gaskets in their sealing ability.
- Using any type of sealant on the plenum rubber gaskets will only cause a come-back later, so install these bad boys dry.
- I recommend also replacing the lower intake manifold gaskets too (since you already have everything off).
- If your vehicle has over 100,000 miles, replace the intake manifold gaskets, because they will eventually (more sooner than later) start leaking engine vacuum.
- This will cause a misfire P0300 code, rough idle and a Lean air-fuel mixture condition.
- The intake manifold gaskets also need to be installed without any type of sealant.
- Replace all of the spark plug boots.
- The spark plug boots can become a source of a misfire since they don't last forever (being exposed to the enclosed heat of the spark plug tubes).
- Your local auto parts will have these in stock.
Spark Plugs And Boots Soaked In Oil
In TEST 3 (or TEST 4, or TEST 5, or TEST 6), you found that the spark plugs and the spark plug boots were covered in engine oil.
This, of course, tells you that the valve cover gaskets are not sealing anymore and both of them will need to be replaced.
Here are my recommendations:
- When replacing both valve cover gaskets.
- Do not use RTV Silicone on them, install them dry.
- Bathing the valve cover gaskets with any type of sealant will only result in a come-back down the road.
- Replace the plenum gasket with a new one.
- Do not use RTV Silicone on them, install them dry.
- Bathing the plenum gaskets with any type of sealant will only result in a come-back down the road.
- I recommend also replacing the intake manifold gasket too (since you already have everything off).
- Do not use RTV Silicone on them, install them dry.
- Bathing the intake manifold gaskets with any type of sealant will only result in a come-back down the road.
- Replace all of the spark plugs.
- Cleaning the oil off of the spark plugs in solvent (like Carburetor Cleaner Spray) is not 100% effective and will eventually lead to the formation of carbon tracks on the spark plug and spark plug boot and then you're back to square one with a misfire again.
- Replace all of the spark plug boots.
- Cleaning the spark plug boots in solvent (like Carburetor Cleaner Spray) will lead to more problems since the solvent will start to break down the rubber the boot is made up of and this will eventually lead to a misfire.
- Also, the solvent does not completely remove the oil and this will eventually lead to the formation of a carbon track (as the oil starts to cook and harden) and you'll have a misfire condition on your hands again.
I can tell you from personal experience that cleaning off the engine oil on the spark plugs and/or spark plug boots with solvent (like carb. Cleaner or brake cleaner) will not work most of the time and if it does, it'll only be a temporary reprieve from the misfire you're trying to solve.
So, if you do go the cleaning route, you'll eventually have to go back and tear everything down and replace them with new ones anyway (more sooner than later). So, it's best to just replace them all from the get go.
Location Of The Fuel Pump Relay
The fuel pump relay in the 2001 through 2007 Ford Escape and Mazda Tribute is found in the fuse and relay box in the engine compartment.
The photo above applies only to the 2001 thru' 2007 Ford Escape and Mazda Tribute. The orange arrow points to the fuel pump relay. If you need to find the location of the fuel pump relay in any other vehicle covered by this tutorial, you'll need to consult the shop manual or the vehicle owner's manual.
More 3.0L V6 Ford Escape Diagnostic Tutorials
You can find a complete list of 3.0L V6 Ford Escape (Mazda Tribute) diagnostic tutorials in this index:
Here's a sample of the tutorials you'll find in the index:
- How To Test The CKP Sensor With A Multimeter (2001-2009 3.0L V6 Ford Escape, Mercury Mariner).
- How To Test The Throttle Position Sensor (2001-2007 3.0L V6 Ford Escape).
- How To Test The Cooling Fan Motors (2001-2004 Ford Escape - Mazda Tribute).
- How To Test For A Blown Head Gasket (2001-2012 3.0L V6 Ford Escape, Mercury Mariner).
If this info saved the day, buy me a beer!
