SHED: TOYOTA HILUX
JIMMY FITS THE FINAL PIECE OF THE PERFORMANCE PUZZLE.
THIS MONTH the Hilux received the final piece to the puzzle for the performance upgrades I wanted: a Diesel Power performance module. The Hilux is already running an aftermarket Terra-tuff front-mount intercooler and a Carbon Offroad threeinch turbo back exhaust, so to take advantage of the increased airflow and to deal with the power loss after the muddies were fitted last month, I installed a Diesel Power Australia tuning module.
Tuning modules have been around for years and have been the go-to performance upgrade for avid 4WD enthusiasts, especially when coupled with an exhaust or other engine upgrade. Diesel performance chips or modules (same thing), go by many names and can work in slightly different ways. Many brands offer claimed power increases from anywhere between 10 and 35 per cent increase over factory figures.
Most chips are easily installed in around 30 minutes and come with all the wiring harnesses and plugs needed to get you up and running. Once installed, the chip/ module works by intercepting the signals coming from the ECU going to the fuel injection rail and then sending modified signals back to the ECU. The control unit sees a lower fuel pressure signal than what is actually occurring and compensates by demanding more pressure from the common rail pump. The increase in fuel pressure increases the amount of diesel each injector fires, thus increasing power with the extra fuel injected. Fuel pressure is increased or decreased based on what you’re doing with the vehicle at the time.
The Diesel Power Australia module I chose for the Hilux is a two-channel chip/ module that regulates fuel rail pressure and turbo boost pressure rather than just fuel rail pressure alone. Boost pressure modification optimises airflow into the motor, so a combination of increased airflow and fuel pressure results in more power and a smoother torque delivery.
As most chip/modules sit upstream from the vehicle’s ECU, the ECU still retains the power to override the chip/module if it is operating outside of the factory specifications of the engine. In the off chance there is an issue, on most vehicles
a check engine light will come on or the vehicle will go into limp mode. This can be cleared easily by disconnecting the chip/ module, or disconnecting and reconnecting the vehicle’s battery. The Factory ECU still monitors all parameters of the motor and offers a backstop of protection and reliability.
The Diesel Power Australia tuning module came with everything needed for a relatively quick and easy installation on the Hilux, plus it came with a synthetic bag with a Velcro fitting strap to keep it tucked away and safe in the engine bay. There are 15 settings on the module (1 to 9; A to F), offering a claimed increase in power up to 25 per cent above factory. This module has been Tuv-approved and verified in Germany to meet strict performance guidelines and performance claims. Setting 9 will give you the claimed increase in power with a factory vehicle but with additional modifications; turning it up to setting C saw the sweet spot of performance. Wind it up too much and you will have a decrease in power as you are flooding in more fuel and not making the optimum burn.
The setup comes with a handy bypass plug, which, when plugged in, returns your vehicle to standard tuning without having to remove the harness. This came in handy when deciding which setting I liked and how much difference it made, as I drove the vehicle for a while on a particular setting then plugged in the bypass to compare to factory settings. Turning it all the way up to F made a noticeable difference, but was a bit of overkill and there was the looming potential of a check engine light coming up on the old Hilux, which I’d prefer to keep as reliable as possible.
For now I’ve settled on the setting C, which provides enough power to counteract the power being robbed by the bigger tyres fitted and should provide reasonable fuel efficiency. Once some significant highway, around town and 4WD kilometres have been racked up, I’ll report back on the overall fuel consumption.