There are five powertrains to chose from. All of the petrols are 1.0-litre turbocharged three-cylinder EcoBoost engines, one with 95PS (70kW), another with 125PS (92kW), a 48-Volt mild-hybrid with 125PS (92kW) and a 155PS (114kW) 48-Volt mild-hybrid. The diesel is a 1.5-litre with 120PS (88kW).
Augmenting Ford's familiar three-pot turbo triple is a hybrid system comprising a beefed-up starter/generator driven by a front belt drive. It stores braking energy in a lithium-ion battery and supplements or replaces the engines’ torque output with an additional 50Nm (37lb ft) when pulling away or overtaking to boost performance, or fuel economy, or both. Ford claims it gives 50 per cent more torque at low engine speeds and allows the use of a lower compression ratio and a bigger turbo to increase top-end power. The engine can also cut one cylinder on light throttle loadings to increase economy.
With its extra electric torque, the engine pulls hard from low on the rev counter. As the Americans say, however, there's no substitute for cubes and this boosted 1.0-litre isn't a patch on Ford's 1.5-litre turbo triple Dragon engine, fitted to larger models including Focus. On occasion, the Puma feels classically turbocharged, with a slight turbo lag on the throttle at the top end of the rev counter, a tendency to dump boost between gear changes and a strange delay in recharging effect when you lift off the throttle, which is almost like a double-tap on the brake pedal. It's a bit noisy when you press on, but it's by no means a bad noise. WLTP Combined fuel consumption is 50.4mpg and CO2 emissions are 127g/km.
With the Fiesta's suspension system, the 1.2-tonne Puma isn't the most sophisticated riding car, but the ST-Line X gets uprated springs and dampers, anti-roll bar and specially engineered rear twist beam, which helps calm things. The ride is acceptable and while there's a lot of initial body movement and roll, it is well controlled. The steering is beautifully progressive and accurate and that makes this car more fun to drive than it has any right to be. The brakes have a strong initial bite but tend to lose effectiveness on long descents.