What Is A Diesel Tuner?

These little electronic gadgets, sometimes known as programmers, engine performance tuners, chips, or gauge tuners, are used to manage and optimize engine performance on diesel trucks. The phrase “The term “chip” refers to the device’s silicon integrated circuit. The ability to go beyond the vehicle’s firmware to modify the engine’s “tune” to the driver’s individual needs is referred to as “programmer.” Some variants come with a “The driver can watch a “gauge” while driving to see how the device is assisting him or her.

A programmable tuner is a single-purpose mini-computer that contains an on-dash or window-mounted monitor and control panel, as well as the appropriate leads to link with the factory engine control module, and can be purchased as an aftermarket item.

What does it mean for a diesel to be tuned?

It entails connecting to a diesel engine’s ECU and changing the parameters to make the engine function how a driver or fleet manager want. Tuning can be done to increase fuel efficiency. It can be done in such a way that the engine’s performance is improved.

Do diesel tuners really work?

Yes, a tuner should theoretically improve your truck’s fuel economy by enhancing engine efficiency. The highest fuel economy advantages are often seen with tunes ranging from 65 to 90 additional horsepower.

What does a tuner do for a truck?

Is it possible to boost the performance of your diesel pickup truck with an engine tuner (chip, module, or programmer)? Yes, in a nutshell, but a more detailed explanation is required.

While aftermarket performance product makers say that aftermarket performance products can add 3-4 mpg, the real savings, if any, are highly dependent on how and where you drive. Performance goods, by definition, are intended to boost engine output. A plug-and-play Juice Attitude CS programmer from Edge, for example, is said to give 150 horsepower and 360 ft-lbs of torque to a Dodge Ram 2500 with a 6.7L Cummins engine (not advised for stock vehicles).

That’s great for smoking Corvettes off the line, but it’s not going to save you money at the gas station. Indeed, the greater horsepower may make it impossible to keep your foot off the accelerator, resulting in higher engine wear and stress on your transmission and drivetrain. Simply put, you risk reducing your truck’s lifespan, voiding the manufacturer’s warranty, and increasing your chances of being pulled over by the highway patrol.

An engine tuner, on the other hand, could be your best friend if you pull big equipment, climb mountainous terrain, or travel long distances.


Manufacturers like as Edge and Bully Dog provide a Mileage Coach to assist you evaluate, monitor, and reduce gasoline use to ensure you’re on your best behavior.

Bully Dog also makes digital watchdog gauges with speed limiter adjustments, diagnostic reader, and driving coach for Caterpillar, Cummins, Detroit, Mercedes, and Paccar engines, as well as an ECM tuner with economy tuning, economy/power tuning, and custom tuning for Caterpillar, Cummins, Detroit, Mercedes, and Paccar engines. The Caterpillar ECM tuner claims a 15 to 18 percent improvement in power and a 6 to 12 percent increase in fuel efficiency for fleet owners.

An engine tuner’s appeal is that it allows you to modify your truck in a variety of ways, from towing to off-road racing, all by flipping a switch or tapping a touch screen.

For example, the Edge Juice has six on-the-fly power levels (25 hp, 70 ft-lbs; 40 hp, 90 ft-lbs; 50 hp, 120 ft-lbs; 65 hp, 160 ft-lbs; 80 hp, 200 ft-lbs; and 150 hp, 360 ft-lbs), as well as a stock (level 0) setting when necessary. It has a 4.3-inch touch screen and an optional backup camera for simple trailer attachment.

The TS Performance Stryker Injector Duration module promises up to an additional 135 horsepower and 200 ft-lbs of torque, as well as 3-4 mpg benefits.

Engine tuners, as the name implies, tweak your vehicle’s computer settings for best performance, such as injection timing, fuel/rail pressure, and injector pulse width.

Engine tuners range in price from around $350 to several thousand dollars for Class 8 truck models, depending on the bells and whistles you want.


Jason Maki, owner of K & S Service Center in Weston, Wisconsin, provides a full line of Edge, Bully Dog, and H & S Performance diesel engine performance items.

“They all do different things,” he explains. “You get a bit more efficiency, a little more performance, and a little more economy.” And it is exactly what the majority of folks are seeking for.

“Diesel performance was a significant market in the late 1990s and early 2000s,” Maki recalls. “With simply a programmer, a module, or a chip, someone could get 50, 80, 100, or 140 horses out of their truck.” However, once you reach those higher horsepower levels, you’ll run into problems.

“You normally don’t see a problem for guys just seeking for economy, but for guys who want enormous power, you wind up having to do extra work on the engine and transmission.”

Even if today’s tuners are compatible with modern diesel emission systems, Maki claims that higher pollution rules, such as the usage of urea and diesel particle filters, have reduced demand for performance items in recent years. Keep in mind, however, that removing an emission system is unlawful unless the vehicle is being used off-road.

Maki has an engine tuner in his 2014 Dodge Ram 2500 with 6.7L engine, largely for additional efficiency, and claims that performance programmers can add a few miles per gallon and roughly 50 horsepower even with today’s tighter pollution rules.

Is it really worth spending $350 for a modest increase in fuel economy, especially with today’s lower fuel prices?


“He adds, “It depends on what you’re doing.” “Probably not if you’re just running around town. However, if you drive a lot of miles or travel for work, these devices can be useful. If you gain 2 miles per gallon and drive 500,000 miles, it adds up.”

Maki, a Cummins dealer, warns truck owners that installing an engine tuner may violate their warranty.

“He says, “We let them make that decision.” “But once they’re out of warranty, anything goes.”

Most engine tuners include a cable that may be run up the door seal to a window-mounted monitor and plug into the vehicle’s onboard diagnostics port beneath the driver’s side of the dash. It takes roughly 15 minutes to complete the installation.

When changing tire sizes, tuners can be utilized for engine diagnostics, performance testing, and speedometer calibration. They can also be updated via the Internet.

Maki advises speaking with a local dealer before purchasing an engine tuner on the internet.

Do tuners hurt engines?

If done correctly, ECU tuning does not harm your car’s engine. A good tune-up will enhance your car’s fuel economy, but maintenance is required more frequently. Extreme tuning, on the other hand, may have an impact on the engine’s longevity.

Why do tuned diesels smoke?

It’s difficult to discuss diesel engines and diesel tuning without mentioning smoke. It’s a hot matter of argument, and there’s a lot more to it than you may think. Whether you’re willing to accept a little smoke for maximum performance or prefer to keep under the radar with a smoke-free tune, it’s a hot topic of debate.

Although visible smoke from a vehicle’s exhaust is not restricted to diesels, most of us associate smoke with the black smoke produced by some tuned diesel automobiles. Soot is black smoke that comes from the tailpipe when some fuel isn’t burned properly. This is usually due to one of two factors: a lack of oxygen or a lack of time for the fuel to burn.

Fueling is boosted in a tuned vehicle to ensure that all of the available air is used up for maximum power. This indicates that there is a lot of fuel in relation to the amount of air; the Air to Fuel Ratio is a measurement of how much fuel there is in relation to how much air there is (AFR). The lower the AFR, the more smoke can be seen.

There is a point at which the volume of air going through the engine is insufficient to allow all of the fuel to burn cleanly; it is at this time that the first haze of smoke appears. There will be more smoke if more fuel is added after this point.

At full throttle, when the most gasoline is injected for greatest power, black smoke is usually visible. Poorly adjusted automobiles, on the other hand, can emit thick black smoke practically all of the time. During regular cruising or mild driving, there is no need for a vehicle to emit black smoke; there should always be enough of air and a high AFR.

In general, the presence of black smoke does not necessarily indicate that an engine is in poor condition. It’s an immediately apparent sign of the vehicle’s Air to Fuel ratio; if you see an increase in black smoke levels, something is causing the Air to Fuel ratio to rise. Because the ECU controls the fueling, it’s much more likely that anything is lowering the amount of air available.

If you’ve recently had an ECU map and are only now stopping to smile and gaze forward, the thick black streak in your rearview mirror is most likely the result of a too exuberant tune running for an extended injection duration.

You most likely have a boost leak or blown a pipe if you can hear the turbo spooling up louder, hear a hiss, or recently heard a popping noise. If this is the case, you should be able to see visible oil around the leak’s path (commonly the VW clip connectors).

Another achilles heel of many diesel engines is the vacuum system. Because the turbo actuator is controlled by vacuum, even a small leak may result in underboost, and the VNT mechanism may become stuck, necessitating a new turbo.

Another source of black smoke is faulty injectors, which are commonly encountered in high-mileage engines (and lack of power). Some companies promote magic remedies that you may put in your diesel tank, but they rarely work on a high-pressure fuel system. The injector nozzles are a worn component that are usually past their prime after 100,000 km.

We constantly ask our customers this question, but it’s not a straightforward one for them to answer or for us to advise on the quantity of visible smoke that is acceptable. You can’t expect any engine setup to produce 100 percent of its power potential while also producing no visible smoke; as a rough estimate, you’ll have to lose up to 10% of peak power and torque to achieve this.

After a certain point (each engine is different), no amount of fuel will enhance the power output, and long before this point is reached, there is a period of diminishing returns, in which the amount of smoke produced for a little gain in power increases dramatically. Even if a customer doesn’t care about smoke or even says they want as much as possible, we still have a responsibility to ensure we aren’t adding fuel unnecessarily, thus testing is required to determine these ‘limits.’

Excessive smoking has consequences that extend beyond irritating the local cops and those following behind. Extra heat is generated, and this hot gas passes through the pistons, head, valves, manifold, and turbo, raising their surface temperatures. This heat has to go someplace, and as the water and oil cooling systems become saturated, the materials begin to fail, which is why VNT mechanisms and pistons melt or heads shatter.

Exhaust gas temperatures (EGT) can easily approach 1000°C, which is a serious worry because aluminum melts at 660°C. Fortunately, a decent engine package will be suitably cooled, and the cold new air from the intercooler will keep the surface temperatures below melting point. In ordinary tune, the piston bowl area is the part of the engine closest to melting, therefore we take great care not to push too hard and cause permanent engine damage.

It’s vital to keep in mind that, regardless of the tune, a car with a DPF will rarely create black smoke. Because the DPF can trap all of the soot produced by the engine, this is the case. If a car with a DPF has a’smoky’ tune, all of the smoke will clog the DPF instead of leaving via the tailpipe. This also means that if a car’s DPF emits visible smoke, it’s quite likely that the DPF has been removed or damaged.

Are diesel tuners illegal?

Smog Check inspections are necessary for California citizens who own diesel pickup trucks; diesel tuning products that are not covered by a CARB E.O. number are running illegally and will result in an inspection failure.

“We have always supplied ‘Clean Tune’ Technology at Banks.” Other tuning companies have applied for the E.O. procedure, but none have had the same level of success as us in terms of Executive Order numbers being issued. “I feel that selling clean products is in my best interest and the best interest of my consumers in this day and age of emissions laws,” said Gale Banks, president.

What’s the difference between a tuner and a programmer?

Performance tuners and power programmers are practically the same thing. The terms are frequently interchanged. Both provide power increases for your car, truck, or SUV and interact with your vehicle’s computer.