Ford 4.6 Firing Order

Mechanics know that a vehicle’s firing order is important. The correct firing sequence decreases, if not eliminates, engine vibrations. But what exactly is a Ford 4.6 engine firing order?

The Ford 4.6 engine firing order is 1-3-7-2-6-5-4-8. Its proper sequence is vital to the smooth operation of the engine. Also, it affects the engine’s efficiency and reliability in Ford F-150 pickup trucks and other medium-duty trucks under the F Series.

Read on to learn more about the Ford 4.6 firing order, including its importance, how it works, and its relation to cylinder numbering.

The firing order is 1-3-7-2-6-5-4-8 for the Ford 4.6 engine. Its correct sequence is vital to the smooth operation of the engine. Also, it impacts the engine’s efficiency and reliability in F150 pickup trucks and other medium-duty trucks under the F Series.

Ford 4.6 features eight cylinders arranged in a sequential manner starting from front to back. This is in 2 banks of 4 cylinders on each side. Its firing order is the same as all Ford V8 engines except the Coyote 5.0.

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Ford 4.6 Cylinder Numbers

The sequence wherein the Engine Control Module (ECM) fires spark plugs in the Ford 4.6 V8 engine begins with Cylinder #1, located on the left front. Next in the firing order is Cylinder #3, located on the same side. The next one is Cylinder #7, located on the second bank on the right side.

Then, Cylinder #2 is fired next, followed by Cylinder #6 and #5. The last ones in the firing order are Cylinder #4 located on the left-back and Cylinder #8 located on the right back.

The Ford 4.6 is a V8 modular engine that features eight cylinders with eight spark plugs. It is arranged so that four cylinders are in a single row. This row is positioned at an angle of 90 degrees to the second row.

The Ford 4.6 cylinder numbers begin from one to four on the left bank, from front to back. The cylinder numbering starts from five to eight on the right bank, from the front radiator side to the back.

How Does the Firing Order for a 4.6 Ford Work?

Let’s talk about the two ignition control system types associated with Ford 4.6 modular engine designs. They are the following:

Waste Spark Ignition System
Coil on Plug System

1. Waste Spark Ignition System

The Ford 4.6 engine had earlier versions that featured the waste spark ignition system. Its ECM controlled it.

Under this system, the engine is equipped with two coil packs. Each group consists of four wires. They are all connected in a pattern to enjoin with their corresponding spark plugs on cylinder banks.

The ECM simultaneously sends a signal to two cylinders. Even if only a single cylinder needs ignition, the other is on the exhaust stroke. The spark energy to such a plug then wastes out. This is the reason why it is called the waste spark ignition system.

Also, since there are two plugs simultaneously controlled, you will observe four signal wires. This will come from the ECM and down to the coil packs.

2. Coil on Plug System

The Coil on Plug ignition system was initially introduced by Ford in its 1999 Ford Mustang model. Under this design, there is a coil separate for every spark plug. Each of these plugs is controlled by the ECM directly. It does not have any distributor coil attached in the middle.

You will observe eight wires that start from the control module and down to each spark plug on all cylinders. The Coil on Plug system is generally called the Distribution Less Ignition System, also known as the Distribution Less Ignition System.

A sensor on the camshaft or the crankshaft detects its position. This is to identify the next piston coming up to the Top Dead Center (TDC) and the one that requires ignition.

The ignition module on ECM receives a signal from the sensor. The ECM triggers the coil for the corresponding spark plug, then fires. The ECM repeats this procedure in a predefined sequence saved in its memory.

Do All Ford Vehicles with 4.6 Engines Have the Same Firing Order?

All Ford vehicles equipped with 4.6-liter V8 engines have similar firing orders for spark plugs. This means that it can be from Ford pickup trucks to Ford sedans.

A similar firing order enables the Ford vehicles’ smoother and noiseless operation. At the same time, it delivers maximum power extraction from the engine.

Also, the latest Ford V8 engines that form part of the modular family all have a similar firing sequence. This is regardless of the displacement length, except for the 5.0 Liter Coyote engine.

What Causes the Wrong Firing Order in Ford 4.6

Several factors contribute to the spark plug activation’s correct order. Some of these are the distributor connections, the signal wiring from the computer, and plug coils. It also includes spark plugs, the camshaft position sensor, and the crankshaft position sensor.

So, what causes the wrong firing order in Ford 4.6 engines? Some of these are the following:

ECM Malfunction
Broken Crankshaft Position Sensor
Faulty Wiring to Spark Plug
Worn Spark Plug

Let’s briefly discuss each one of them:

1. ECM Malfunction

When it comes to the Ford 4.6 modular engine, all spark plugs are controlled by a computer or the ECM. It is assisted by spark coils, sensors, and a pre-programmed sequence in its memory.

If there is a faulty ignition module or damaged coil packs, they can inaccurately activate the spark plugs. This will then lead to other car issues.

2. Broken Crankshaft Position Sensor

The crankshaft/camshaft position sensor sends information to the ECM about the position of the initial spark to be fired.

The computer will likely start firing the wrong spark plug if it sends inaccurate information. This will cause the whole sequence to be disturbed accordingly.

3. Faulty Wiring to Spark Plug

The engine computer or the ECM sends information to the spark plug coils. This is done through distributors or direct connections. It all depends on the ignition system.

It can activate when the valve is closed to give you an idea. But it can also mean that it can activate when the piston is in exhaust position.

4. Worn Spark Plug

To ensure that the firing pattern is correct, you must ensure that the spark plug is in good working condition. If there is a faulty spark plug or a misfiring one, it will result in firing with skipped positions.

A worn spark plug has several symptoms. These include failure of the vehicle to start, noisy operation, and vibrations.

Again, what is the firing order for a Ford 4.6 engine? The 1990-2014 Ford modular 4.6L modular V8 engines’ firing order is 1-3-7-2-6-5-4-8.

Disadvantages of Wrong Firing Order in 4.6 Ford Engine

Engine designers fix the firing order to ensure engine balance. This also reduces excessive engine vibrations.

There are, of course, disadvantages of a wrong firing order in a 4.6 Ford Engine. Some of these are the following:

Excessive Vibrations
Failure of Engine to Start
Bad Engine Sound
Engine Backfiring
Poor Engine Performance

Let’s briefly discuss these points:

1. Excessive Vibrations

If cylinders fire all simultaneously, your engine will most likely get maximum power at that very moment. However, there will most likely be no power in the succeeding instances.

This will then lead to jerky engine operation. Also, it is important to maintain a smooth distribution of energy during the whole combustion cycle. This can be done through a correct firing order.

The crankshaft design is also associated with the order of spark plug activation. If there is an issue with the sequence, you will most likely notice jerky and unbalanced operations. There will also be random motion filled with vibrations.

2. Failure of Engine to Start

If there is a wrong firing order, such as a delayed one, the engine will not perform accordingly. With the firing order, there is a sequence of steps followed. It starts with a valve opening, then the proper air and fuel mixture injection. The next step involves the compression and then the spark plug firing.

3. Bad Engine Sound

If there is an incorrect firing order of spark plugs, you will notice a noisy operation. A noisy process can result from different factors. Some of these include the simultaneous firing of two cylinders, the collision of the pistons with the valves, incomplete combustion, and backfiring.

You should maintain the proper sequence of spark coils and the timing belt or chain.

4. Engine Backfiring

Have you heard of an engine running with a big sound similar to a bang? Such noise results from ignition in the exhaust chamber or intake manifold. This is commonly called backfiring.

If the wiring order in the distributor changes, it will disturb the whole sequence and backfiring. Unfortunately, this will damage engine parts and power and fuel waste.

5. Poor Engine Performance

A proper firing sequence is essential in delivering maximum power to the crankshaft. Each cylinder fires up based on a predefined time in a sequence.

If you encounter a poor engine performance, it most likely results from the wrong sequence, backfiring, misfiring, or not firing. This will also result in rough idling or failure to perform efficiently.

FAQs – Ford 4.6 Firing Order

Does the Firing Order Depend on the Cylinder Numbering?

The firing sequence greatly depends on cylinder numbering. The cylinder numbers are used to identify the position of the spark plug that will fire next.

Can You Change the Firing Order on the Ford 4.6 V8 Engine?

You can change the firing sequence on Ford 4.6 engines by swapping the signal wires from the ECM to the coil packs in the Coil on Plug system. You must change the connection order while it is in the ignition system with the distributor.

However, while it is true that you can modify the firing order, it can lead to negative effects. For instance, it can cause damage to its parts, it can increase vibrations, and can decrease engine performance.

You can modify the firing order only if you are an expert in this field.

In Closing: What Is the Ford 4.6 Firing Order

The firing order is 1-3-7-2-6-5-4-8 for the Ford 4.6 engine. Its correct sequence is vital to the smooth operation of the engine. Also, it impacts the engines’ efficiency and reliability in F150 pickup trucks and other medium-duty trucks under the F Series.

So, if you are wondering how important the firing order is, it is essential to the performance of your Ford 4.6 engine.