For the last five years, every time he filled his petrol tank, Mr Weng Liew would reset the mileage counter on his car so as to monitor his fuel consumption.  

The night his Honda CRV was stolen from a multi-storey carpark in Jurong West, MrLiew had just filled his tank in preparation for a trip to Malaysia the next day.

But when he recently recovered his lost car, he realised the meter read 7.7km.

He said: 'The petrol kiosk (where I topped up) is around 2km away from my house. Who clocked the other 5.7km if the car was towed?'

Mr Liew was frustrated by Kah Motor's insistence that his car had been towed despite his belief that it had been driven away.

Kah Motor said the anti-theft system for the cars would have kicked in and the cars would not have started and be driven off.

Mr Liew is one of the five Honda CRV car owners whose vehicles went missing late last month.

Upset that their cars were stolen despite the anti-theft system, Mr Liew yesterday rallied other Honda CRV owners to sign a petition.

The owners of the stolen cars believe the safety device - an engine immobiliser system - did not do its job.

The system is supposed to prevent the car from being driven away by anyone without a key that is synchronised with the car. It does so by cutting off the engine.

The 30 drivers who signed the petition yesterday belong to a Honda CRV owners group called the CRaVers Club, which has some 300 members.

After recovering his car, Mr Liew said he did an experiment by driving from his home to the spot where the cars were found.

The distance: 5.7km.

Mr Vincent Ng, 43, product manager at Honda distributor Kah Motor, defended the cars' system.

Owners: Why didn't the immobiliser work?  

Mr Ng: There is nothing wrong with the immobilisers. The thieves may have broken in but the security system prevented them from powering up the car and driving it away.

If an unauthorised key was used, the engine may be able to start cranking, but once drivers attempt to change the gear from Park to Drive, the engine stops immediately.

Owners: If the cars could not have been driven away by the thieves, how did they disappear from our carparks?

Mr Ng: Only the police can answer this question because investigations are ongoing.

The damage on the cars seems to indicate that the cars were towed away.

On some of the cars, there are symmetrical dent marks on the left and right fenders, and damaged front bumpers.

There were also scratch marks on the roof of one of the cars. These may have been caused when the thieves hooked the cars up to be towed away.

Owners: But wouldn't the height limit on the multi-storey carpark prevent thieves from towing the cars away?

Mr Ng: Even if a tow truck cannot enter a multi-storey carpark, there are many other possibilities, such as the thieves pushing the cars to another place before towing them away.

As the CRV is a four-wheel drive, to push and steer the cars, the thieves have to break the wheel lock and the steering lock by entering the car and shifting the gear from Park to Neutral.

Owners: Our cars can be started using any key, even our house keys.

Mr Ng: This is not true. The car would merely be cranking, but the engine would not have started.

Cranking is the point when the engine is trying to start. When someone shifts the gear from Park to Drive, the cranking stops immediately.

There is no way the car can be driven at the cranking stage.

Owners: There are vehicle immobiliser bypass kits being sold in the market. How is the immobiliser on our cars protected against that?

Mr Ng: Such bypass kits would not work on the CRV's engine immobiliser because the one in the car is a fourth-generation engine immobiliser which generates a rolling code each time the car key is inserted.

These kits would work on older versions of the immobiliser, which used a fixed code.