The Indian market has opened up considerably in recent times and the demand for luxury cars has witnessed an upward trend with a concurrent rise in people’s spending power. However , with petrol prices ever on the rise , the fuel question confronts all luxury car buyers as well. Even if they buy those excellent machines , will driving them around be an affordable proposition? Well , we at Car India are always happy to tackle such issues. Therefore , we decided to check for ourselves how efficient a luxury sedan can be.

The idea was conceived when Aspi drove the A6 for the first time in Sicily , where Audi claimed this car to be highly efficient. We decided to figure out how long it would go in just One tankful of fuel. Diesel was the obvious choice , since oil burners are increasingly being preferred to petrol cars. We decided upon the Marina Beach in Chennai as our starting point , from where we would drive to the Marine Drive in Mumbai. In other words , from the south-east coast to the west coast of the country.

 

A rough calculation showed us that we had 1 , 350 kilometres to cover in a tankful , that is , 75 litres of diesel. A challenging task indeed. The journey required us to drive the car in real world conditions (unlike the test rollers on which the Automotive Research Association of India calculates efficiency) and tackle everything from chaotic traffic , toll-booths , food halts , uphill/downhill stretches and low-visibility driving at night and still achieve about 18 km per litre to meet the challenge. Aspi was quite confident about the efficiency of Audi's 2.0-litre oil burner and decided to drive all the way himself. i decided to drive the back-up Q5 and so flew down to Chennai to undertake this memorable drive.

 
The A6's diesel tank filled up to the brim and with tyre pressures checked , we left Chennai at 3.30 am. The initial three hours of drive was in poor visibility with our eyes still refusing to remain wide open. After about 300 km on the trip meter , we decided to take our first quick halt for a cup of coffee. It was rather a must to ward off sleepiness. A cup of strong coffee later , we were back on the road. The task at hand was to continuously keep monitoring the on-board computer that displayed a lot of information , including how many kilometres had been travelled , how much fuel had been consumed , what was the overall efficiency so far , what was the instantaneous efficiency being delivered and the approximate range that the car had before running out of fuel.

 
On the driving front , we were determined to travel at speeds that were normal and practical for Indian highways. Aspi decided to stick to the manual mode and drove between 90 km/h and 100 km/h. At that speed , the engine of the A6 was comfortably spinning between 1 , 400 and 1 , 500 revs in the top gear of the eight-speed transmission.

The good condition of the roads was one important aspect highly conducive to our long journey. Wide , four-lane highways throughout the region we travelled through were a boon indeed. With no diversions called for , there was no need to slow down and pick up speed later , which saved us a bit of fuel for sure. However , we found ourselves embroiled in heavy truck traffic as we approached Hosur. The fuel efficiency indicator that showed 5.2 litre/100 km until now shot up to 5.5 litre/100 km in the traffic.

 
Crossing Hosur was painfully slow , but once we hit the NICE Road that bypasses Bengaluru , we could look forward to a constant pace. Passing through cities and towns , the comfortable Audis made sure that we didn’t have to take a halt on account of driving fatigue. Both the cars , especially the A6 , offered such an excellent drive that it was only the trip meter that made us aware of how long we had been driving.

By 1.30 pm , we crossed Hubli and started looking for a decent restaurant where we could have lunch. At about 2.00 pm , with the trip meter showing almost 700 km , we halted for the meal. The consumption on the A6 so far showed 5.2 litre/100 km and it still had a range of 620 km. More than half the distance had already been covered , thus making us confident of achieving our goal in just one tankful.

 
Apart from the couple of stop-overs for coffee and food , there were many more for paying the mandatory toll all along the route. At one point , one really gets fed up with those frequent halts to pay the toll. However , one also has to bear it in mind that if it were not for those toll roads , we would not be able to drive on such smooth tarmac , bypassing almost all the cities and villages en route.

By evening , we entered Maharashtra and passed Kolhapur , with the road cluttered up by heavy lorries. Nevertheless , we skilfully managed to maintain the average speed. If fuel was one constraint for us , time was another. Though there was no time limit as such for this journey of ours , human body has its own limitations. 

 

By 8.00 pm , we approached Khed-Shivapur on the outskirts of Pune where we encountered heavier traffic , which disturbed our consistent pace. It was 8.30 pm and time for our third and final halt during this drive for dinner. Post-dinner , we had done over 17 hours of driving. Fortunately , we had sparse traffic to tackle either on the Pune-Mumbai expressway or within Mumbai , which we would enter  late in the night.

Towards the end , as we climbed down the Lonavla-Khandala section and entered Mumbai , the fuel efficiency indicator read as low as 5.1 litre/100 km , which translated into approximately 19.6 km per litre. We were stunned by this reading. A small car delivering such efficiency was understandable , but from a luxury sedan like the Audi A6 it was rather hard to digest.

 

We reached the Marine Drive in Mumbai by 12.00 midnight with fuel to spare for another 120 km , according to the on-board computer. A distance of 1 , 337 km had been covered in 20 hours and 30 minutes and the fuel consumed was less than 75 litres (the tank capacity). Upon refilling , the tank took 70.8 litres of diesel , which translated into an overall economy of 18.9 km per litre. 

 

Now that the feat was achieved , we wondered about what really contributed to this. We have to hand it to the engine first. The TDI engines have always proved to be highly efficient. Secondly , to the eight-speed multitronic transmission that let us drive at high speed but at revs that were a mite over idling speed. Apart from these drivetrain components , what also played an important role was the steel-aluminium construction of the body of the A6 that saves approximately 15 per cent of weight compared with a conventional all-steel body.

Aerodynamics is another factor , which Audi have worked upon extensively to improve the efficiecy by reducing the air drag. The Ingolstadt company claims to have reduced air drag by 19 per cent from the previous A6. Audi have also incorporated a new thermal management system that brings the engine up to operating temperature quickly so that the period after a cold start , during which frictional losses are higher , is reduced and fuel-efficiency is improved. Though this technology had a little role to play in our drive , we are sure it would improve the car's efficiency in day-to-day use.

 

All these factors put together contributed to something that was beyond our expectation. Travelling such a long distance in less than a tankful of fuel in a luxury saloon like the A6 was a veritable feat.

If anyone says that these cars are not affordable owing to the rising fuel prices , Audi have got an answer and , going by our experience , it’s phenomenal!

---

Content courtesy: 

---

---