This topic often creates different opinions among readers. Some drivers are actively advocating for them while others don't see much of a use. At the end of the day, each to their own, different drivers, different vehicles, different needs.

But let's start by clarifying, what is a throttle controller, and how do throttle controllers work?

We can define electronic throttle controllers as tech devices that sharpen (or soften) a vehicle's throttle response by modifying the voltage signal from the fly by wire pedal assembly. The driver can then tune the response from the accelerator pedal and eliminate or reduce throttle accelerator lag.

Accelerator lag is the experience when you put your foot down on the accelerator pedal and you get a poor or very slow response from the engine. This can range from frustrating while trying to sprint in an opening on a busy roundabout to dangerous when trying to overtake a caravan doing 90km/h in the middle lane of the highway while trying to avoid any "flying" work utes in the right-hand lane.

In addition, to increase throttle response, some controllers offer a decreased, mode which can offer fuel economy savings and more gentle control in tricky 4x4 situations.

Back in the days when nothing but the most basic electronics existed in cars, we were relying on conventional mechanical cables - attached to the accelerator pedal at one end and the throttle assembly at the other.

Using a petrol engine, for example, the throttle body assembly controls the amount of airflow into the engine via a butterfly valve, or plate, which opens or closes depending on the pedal position. As you pressed down on the accelerator pedal, the cable pulled the throttle open and voila!

Nowadays on most modern vehicles, electronic sensors and actuator motors have replaced the cables. The sensor at the pedal tells the vehicle's ECU (computer) how far down the pedal has been pressed and in turn, the ECU sends a signal to the actuator to increase airflow to the engine.

The whole process is easily explained in this video

credits to Engineering Explained

The most popular and recent electronic controllers on the market plug straight into the wiring harness at the accelerator pedal in the blink of an eye.

Check this demo from Ultimate9 EVC

It's fair to say that these throttle controllers don't increase horsepower. They don't in any way control fuel mapping, air to fuel ratio or injection timing. They only change how the throttle responds by eliminating any delays in the throttle system.

Okay - but isn't it just easier to press the accelerator harder?

Not quite. In some vehicles when you put your foot down on the accelerator pedal, not much happens - or it happens slowly. This dead zone has lessened response so pressing hard with your foot won't get you far. This is often built into the ECU by vehicle manufacturers to offer better fuel economy and to smooth out acceleration.

The throttle controllers' job is to turn this dead zone into an action zone which opens the throttle earlier in the pedal stroke. This process cannot be done by pressing the pedal faster or harder.

At All Four x 4 Spares, we stock several market-leading throttle controllers from manufacturers Ultimate9 EVC and SAAS S-Drive Throttle Controllers

All our customers who purchased these have all been quite satisfied, pointing out that their 4WD has quicker access to power and the fact they now enjoy a more sporty drive.

With the wide range of vehicle configurations the type of mapping required by the sensors can vary. Rather than a one-size-fits-all product, the controllers we sell are customised solutions taking into account vehicle make, model, engine and induction type (turbo or naturally aspirated).

For those towing, throttle controllers can be quite useful when you drive off as they will get the vehicle up to speed more easily so you'll be using less fuel and less motor strain.

Then the good thing about some of these higher quality throttle controllers is that you can pick the settings based on your driving mode. For example, some throttle controllers come with 21 different variations shown below:

OFF-ROAD MODE (7 sensitivity settings) ... Extra-sensitive control for low-traction surfaces and low-range rock-crawling. It doubles as the economy mode for long-distance cruising.
TOWING MODE (7 intensity settings) ... Instant response for decisive, safer overtaking and merging.
SPORTS MODE (7 intensity settings) ... High-performance response for grunt-on-demand.

Other throttle controllers manufacturers such as Ultimate9 EVC while also offering different settings in Eco mode and Ultimate mode, they also provide an Automatic mode which changes the throttle performance based on the pressure the driver applies to the pedal

Hopefully, this article has cleared some doubts, and if you are considering installing them on your 4WD, check the great range we offer from our great suppliers: Ultimate9 EVC Throttle Controllers and Roadsafe SAAS S-Drive Throttle Controllers