Inigo S. Roces / Kelvin Christian Go | March 22, 2018 11:56
How the RZ4E BluePower diesel makes the mu-X better and cleaner
The massive shift from large gas guzzling engines to the smaller turbo fed powerplants in nearly all new cars today is incontrovertible proof that it’s not about the size, but how you use it. New, more stringent fuel efficiency and emissions standards are causing automakers to rethink the old adage of ‘no replacement for displacement’. That same philosophy is slowly being embraced, not just by the super and sports car makers, but even our favorite everyday brands.
Isuzu is the latest to look to more efficient means of propulsion with its new 1.9-liter BluePower engine finally debuting in our market. First released in Thailand, the new 1.9-liter RZ4E-TC engine slots right between the 2.5-liter 4JK1-TCX and venerable 4JJ1-TCX 3.0-liter. At first glance, it may seem like a downgrade, but the new engine actually produces 14 PS and 20 Nm more, totaling up to 150 PS and 350 Nm.
With the introduction of this new engine, Isuzu can now complement its 3.0-liter Blue Power engine, and offer a broader range of models and trims levels, while still meeting the government’s newly imposed EURO-4 requirement.
Another addition is Isuzu’s new Brake Override System. This new safety feature is designed to provide peace of mind, particularly in panic situations. During events when a child suddenly crosses in front of the car, stomping on the pedals to stop is our typical first instinct. The BOS, ensures that, even if the accelerator were accidentally depressed at the same time as the brake, it would cut off engine power and apply the brake. To ensure consistent safety, it cannot be deactivated.
Naturally, among the first to receive this new engine is the best-selling mu-X. From the outside, there’s little to distinguish it from the 3.0-liter Blue Power model. Inside Isuzu has mildly tweaked the interior with more piano black inserts and barleycorn garnishes for a more upscale feel.
The most palpable difference is in the drive. By now many naysayers may think the new 1.9-liter Blue Power engine is too small for such a large vehicle, but in truth, it feels like an even better match than the 3.0-liter, particularly for city use.
From the moment it’s turned on, the most noticeable aspect is its quieter and smoother operation. There’s a significant reduction in the noise and vibration penetrating the cabin, particularly when idling, making the mu-X feel like it’s powered by a petrol engine.
There’s some significant torque from the engine from the offset, and paired with this manual, can be quite a surprise to most. First gear has been designed to be short to easily get rolling, especially if the car is fully loaded. From there, it’s a much longer second and third, ideal for low to medium speed traffic. In truth, we found ourselves rolling off from second gear, as there was more than enough torque to pull away smoothly. In addition, manual variants like these will be fitted with a gear shift indicator in between the dials, advising drivers when to change gear for improved efficiency.
The small size may lead you to think it’s a rather peaky engine, but the 1.9-liter Blue Power has quite a broad powerband, delivering lots of torque from 1,200 rpm to 3,000 rpm. This makes it easy to cruise along at low speeds in high gear and quickly shift to a lower gear when power is needed. For most everyday situations, the engine is happy to hum along at a littler over 1,100 rpm, easily returning fuel consumption figures of 12-16 km/L even in heavy traffic.
For longer drivers like highway, the mu-X will deliver the same effortlessness, particularly at speeds between 80-100 km/h. It’s only here where the 3.0-liter’s advantage is more evident, as accelerating to overtake or maintaining a higher top speed takes a bit more effort.
Nonetheless, for most uses within the city, particularly commuting from home to work, picking the kids up from school, or even the weekly grocery run, the new 1.9-liter Blue Power seems tailor made. It’s smooth operation, high torque, quiet operation, and most importantly — radically higher fuel efficiency —make it even better suited for a wider variety of light duty and everyday tasks.
Isuzu plans to position the new 1.9-liter Blue Power variants as entry and mid-level offerings, straddling the gap between AUVs/MPVs and SUVs. It’s an appropriate position to fill as the surprising performance of the new engine will appeal to both the fuel conscious and the sophisticated.