The number of cases of motorists caught for illegally modifying their vehicles has plunged this year.
Industry players said this is likely due to the harsher penalties introduced by the Land Transport Authority (LTA), as well as greater consumer awareness of the do's and don'ts.
Between January and October this year, the LTA dealt with an average of 1,184 cases of illegally modified vehicles every month.
This is a 34 per cent drop from the monthly average of 1,795 cases in the same period last year, reversing the upward trend seen in recent years.
In 2014, the authorities dealt with an average of 1,793 cases a month, while in 2013, there were 1,418 cases a month on average, according to LTA data.
The common modifications which run afoul of the law are unapproved exhaust and lighting systems, and overly tinted windows.
In November last year, the LTA introduced a tougher inspection regime to deal with motorists caught more than once with illegally modified engines or exhaust systems.
Those caught a second time will have to send their vehicles for an inspection every six months, over a period of two years.
Those caught a third or subsequent time will have to do this every three months, also over two years.
Inspections are usually only required every year or two, depending on a car's age and type.
The LTA said that as of October, eight vehicle owners have been placed under the harsher inspection regimes.
The stricter inspection regimes are on top of existing penalties of a fine of up to $2,000 or jail of up to three months for first-time offenders.
Repeat offenders can be fined up to $5,000 or jailed for up to six months.
"Modifying a vehicle's engine or exhaust system without due certification and approval can result in inability of the existing vehicle components to handle the increased power or speed," said an LTA spokesman.
"Such modifications may also affect the durability and reliability of a vehicle," he added.
Car workshops say that because of the stiffer penalties, consumers have become more cautious.
Furthermore, with the economy slowing down, fewer motorists are splashing out on modifications.
Mr Kenrick Kuek, 30, who owns MCS Garage, said: "Customers today are more aware of the LTA's rules and regulations, and what are the approved types of modifications."
