How To Test The 2 Coil Packs (Ford 4.6L V8)

Finding The ‘Dead’ (Misfiring) Cylinder

I Have Misfire Trouble Codes:

If your Ford vehicle is registering misfire codes, half the diagnostic battle is over. Now, the most important thing you need to do, is identify which cylinder or cylinders are the ones that the misfire codes are accusing of misfiring.

This is pretty easy, and since it's key to using this test article, I'll show you how in this section.

OK, this is what you need to do to get this show on the road:

1. The first thing is to use the illustration above to identify the cylinder or cylinders.
2. Next, if you have two misfire codes, you need to find out if they are ‘Paired Cylinders’. The ‘Paired Cylinders’ are:
   #6 and #1. So you would have codes: P0306 and P0301.
   #3 and #5. So you would have codes: P0303 and P0305.
   #7 and #4. So you would have codes: P0307 and P0304.
   #8 and #2. So you would have codes: P0308 and P0302.
3. Any other combination of cylinders, like for example if you have misfires on cylinders #6 and #3 or #1 and #2 are NOT ‘Paired Cylinders’.
4. With this info, you can now start at TEST 1: Checking For Spark.

I Don't Have Misfire Trouble Codes:

If you have NO misfire codes but you do have a bonafide misfire condition (and this happens A LOT!), you can still use the info in this article, the most important thing you need to do is identify which cylinder or cylinders are misfiring.

To find out which cylinder or cylinders are the ‘dead’ ones, you're gonna' have to test all of the spark plug wires for spark or do a cylinder balance test. The cylinder balance test is done by disconnecting one fuel injector at a time.

I have written step-by-step instructions on this cylinder balance for the 4.6L and 5.4L Ford engines with C.O.P ignition coils but the instructions will apply to your specific 4.6L with coil pack ignition. You can find it here: TEST 5: Cylinder Balance Test (found at: easyautodiagnostics.com).

OK, once you have found out which cylinders are dead:

1. Using the illustration above, identify the cylinder or cylinders that are dead (misfiring).
2. Next, you need to find out if any of the ‘dead’ cylinders are ‘Paired Cylinders’. The ‘Paired Cylinders’ are:
   Cylinders #6 and #1.
   Cylinders #3 and #5.
   Cylinders #7 and #4.
   Cylinders #8 and #2.
3. Any other combination of cylinders, like for example if you have misfires on cylinders #6 and #3 or #1 and #2 are NOT ‘Paired Cylinders’.
4. With this info, you can now start at TEST 1: Checking For Spark.

More Ford 4.6L, 5.4L Tutorials

I've written several more tutorials that may be of interest to you. These are specific Ford car (pick up, van) tutorials you can find here: 4.6L, 5.4L Index of Ford Test Articles.

Here's a small sample of the tutorials you'll find:

1. How To Test The Camshaft Position Sensor (1997-1999 Ford 4.6L, 5.4L).
2. How To Test The Blower Motor Resistor (Ford 4.6L, 5.4L).
3. How To Test The Fuel Pump -No Start Test (Ford 4.6L, 5.4L).
4. Coil-On-Plug (COP) Ignition Coil Misfire Tests (Ford 4.6L, 5.4L).
5. How To Diagnose Misfire Codes P0300-P0308 (Ford 4.6L, 5.4L).
6. How To Test The Ford EGR Valve EGR Vacuum Solenoid, DPFE Sensor (at: easyautodiagnostics.com).
7. How To Test The Ford MAF Sensor (4.2L, 4.6L, 5.4L) (at: easyautodiagnostics.com).