HOW A TUNING BOX WORKS

These interfere with engine management signals to trick the injectors into adding more fuel, relying on the principal of more diesel equating to more power… which is correct, it does increase a diesel engine’s BHP. Crucially though, there is no control over the amount of black smoke coming out of the exhaust, and no thought is given to how other vital engine management systems are affected.

Too much smoke is undesirable, both environmentally and visually. The black smoke is unburnt diesel fuel with deposits exiting straight out of the exhaust pipe. This results in raised emissions, a higher thermal load on the engine, and poor driveability – with “bucking” a common problem. It is clear what this means for your engine.

Because a diesel box operates independently from the other – increasingly complex – engine management systems, the results of using one can induce undesirable results, such as:

•  The trip computer showing improved fuel consumption, when the reality is entirely the opposite
•  The stability control system’s calibration is affected due to incorrect torque values being applied
•  Loose boxes and wiring left within the engine compartment
•  Automatic gearboxes receive incorrect torque values
•  Torque reduction when shifting gear (for comfort and durability) not retained
•  Diesel particulate filter regeneration is adversely affected
•  The calculation of exhaust gas temperature is incorrect
•  The calculation of service intervals is incorrect
•  Diagnostic systems can bring up multiple error codes