A FLEET arena where 110bhp was the maximum punch from a diesel engine is rapidly becoming old news as carmakers produce oil-burning units to deliver more powerful performance.

Renault's new 2.2-litre dCi common rail diesel engine, offering 150bhp, is the latest in a series of units from manufacturers that produce figures to rival equivalent petrol models.

The Laguna is now offered with the uprated engine, pitching it against tough competition from other diesel manufacturers, lead by PSA Peugeot Citroen and the Volkswagen group.

By adding a 150bhp dCi engine to the Laguna, Renault now has a full complement of power outputs in its diesel stable, with the powerplant taking its place alongside the 1.9-litre dCi which is tuned to offer either 100 or 120bhp.

In hatchback form, the Laguna 2.2 dCi will attract a benefit-in-kind charge of 18% in the first year of the new company cartax system, with CO2 emissions of 167g/km. The Sport Tourer will incur a higher charge of 19% with emissions of 170g/km.

Renault's 1.9 dCi also incurs an 18% tax charge, although the higher list price of the 2.2-litre models means the driver incurs a greater tax bill.

The list price for the Laguna 1.9 dCi Privilege is £18,015 and a 22% tax payer can expect a tax bill of £713 in 2002/2003.

A face off against the same trim level for the Laguna 2.2 dCi, which costs £19,550, shows that the same driver will be looking at a tax bill of £774.

Renault says the majority of the difference is accounted for with the addition of Electronic Stability Programme (a £750 option on the 1.9 dCi) and the addition of variable rate power steering as standard. This year about 30,000 Lagunas were sold - with about 65% to fleets - and the company hopes to sell similar numbers in 2002. Behind the wheel

RENAULT'S new 2.2 dCi unit in the Laguna is designed to offer fleet drivers plenty of performance while keeping company car tax bills low.

I drove the Sports Tourer model, which completes the 0–62mph dash in 10 seconds - shaving one second off the time of its 1.9 dCi stablemate.

Acceleration is not 'neck snapping', but it is delivered smoothly and in a refined way, thanks to the qualities of the common-rail system.

The Laguna 2.2 dCi is equipped with speed-sensitive steering, which claims to be light around town but more precise at speed, although I found it uncommunicative.

However, as a motorway cruiser the 2.2 dCi is difficult to fault, offering low revs and quiet performance at speed.

The new 2.2-litre unit does not turn the Laguna into a performance car.

However, it provides a comfortable drive, with the reassurance of a mass of power always in reserve when it is needed for in-gear acceleration.