Samuel Ee, Business Times 5 Nov 08;
SLUGGISH and sometimes jerky performance seem to have driven a wedge between the Singapore car buyer and compressed natural gas (CNG), with the love affair set for a possibly unhappy ending.
Some cars retrofitted with CNG kits have been causing problems for owners, who say their cars now face a loss of power or worse.
'One owner was so fed up with her CNG car stalling every other day that she drove back to our workshop and told us to remove the entire kit,' says the manager of a parallel import company. The cost of a CNG conversion can range from $3,000 to $4,500, depending on the size of the gas tank installed.
The manager believes the car's petrol engine was not designed for CNG use, so there may be durability issues.
'Unless it is like the Mercedes-Benz E200 NGT, which has a factory-fitted CNG kit,' he says. The Merc is the only such OEM (original equipment manufacturer) model available here.
The executive of an authorised distributor says that his company also faced CNG-related woes.
'We have stopped all retrofitting works and no longer offer the CNG alternative to our customers,' he says. 'There were problems with the ECU (electronic control unit) and engine mapping, which caused a lot of minor problems. There was power loss, the engine stalled and even the trip computer's readings were out.'
He adds that with such serious technical issues involved, the dealership had no choice but to pull the plug on CNG retrofits. Also baffling was that different cars had different problems or none at all.
'The same CNG kit installed in two different cars will have different results,' he says. 'It is probably the lack of expertise on the installer's part - they don't know what to do.'
Gilbert von der Aue, manager of C Melchers, agrees that some CNG installers are less well-trained than others, but he says that 'only a very small percentage of cars are having a small issue'. Melchers is one of the better-known names for CNG retrofits in Singapore, which has a total of around 20 installers.
'Our group does about 55 per cent of all retrofits, and out of all these cars, only 2 per cent have issues where certain cars will have a slight drop in performance compared to petrol,' he says.
He explains that the jerkiness occurs during acceleration and if the driver is 'light-footed'.
'CNG's burning characteristics require more gas to flow in, so you have to adapt to the way of driving,' says Mr von der Aue.
As for the other issues, he says that they could be due to the tuning of the cars, which a less-proficient installer may not know how to perform effectively, or even a problem with the car itself.
'We have seen inherent problems with the existing car, like its compression ratio. CNG technology is very precise, so it is far less forgiving than petrol,' he says. 'It is a proven technology and there are no technical issues for Melchers.'
He attributes the steady drop in sales of new CNG cars to worries about the re-introduction of the special tax and adverse publicity about long queues at the only two CNG public refuelling stations. There is a special tax of six times the road tax for bi-fuel cars such as CNG cars, which can also run on petrol, but there is an exemption until Dec 31, 2009. A review of the special tax will be done closer to the date and some people fear the exemption will be lifted.
The number of new CNG cars has plunged dramatically from the July peak of 419 units. It slipped to 320 cars in August, and further to only 283 units in September.
One parallel importer who used to sell about 20 CNG cars a month now only gets two or three orders. He says that the advantages of these cars - their lower running cost (CNG is cheaper than petrol) and reduced registration taxes (new cars retrofitted with a CNG kit attract a green vehicle rebate of 40 per cent of open market value) - have been overshadowed by adverse publicity and falling petrol prices.
He says: 'CNG is now an old story.'
