At least 17 used cars imported from Germany and Japan have caught fire recently, Civil Defence sources said.
"These cars [mainly meant for the European market] are not suitable to be used in the country, especially during summer when the temperature is very high," the sources said.
Warning people against buying used cars from Europe, an official said: "Cars which are manufactured to suit the cold weather conditions as in Japan and Europe and are imported here are not fit for driving in the UAE and other Gulf countries because of extreme hot weather conditions."
Civil Defence personnel extinguish a fire which engulfed a second-hand car from Japan near a Dubai shopping mall.
However, the officials said cars imported by authorised dealers would face no problems because they are manufactured to suit local weather conditions.
On Monday an used car imported from Japan overheated and caught fire inside the car park of a Dubai shopping mall and was completely destroyed.
Gordon Ferguson, Workshop Supervisor at AAA Service Centre, said: "People should be careful when buying used cars.
"Only those cars which carry the Gulf specification mark should be bought because they are manufactured to suit the climate here.
"European cars which are used in Europe are manufactured to suit climate conditions in Europe and cars which are used in Japan are only suitable for the weather conditions in Japan or other similar situations."
He said: "They are not suitable to be driven in hot weather conditions such as we have in the UAE because of the smaller size of their radiators, pipes and temperature control systems.
"There should be some restrictions on using these cars. Some regulations should be introduced to check the roadworthiness of these cars before they are registered."
Also, he said, people using old cars should take greater care of them because they can catch fire in hot weather if poorly maintained.
"Motorists should have their cars repaired by qualified mechanics at proper garages," he said.
Benny Kurian, workshop manager at Max Garage, said a car blaze is commonly caused by the leakage of oil in the power steering and transmission systems or by electrical faults.
"Any car, whether imported from Japan or locally purchased, is vulnerable to fire if not maintained properly," he said.
Iqbal Dawood, president of the Used Cars Association in the Dubai Used Car Automobile Zone, said European cars imported from Japan have thermostats which are used in cold weather conditions to heat the car.
"Buyers of these used cars are required to make some changes in them before taking them on the road. They should change the radiators as well," he said.
He said 2,000 to 3,000 used cars are imported into Dubai and Sharjah every year.
A number of vehicles also caught fire in Al Ain when the temperature rose to 47 degrees Celsius.
An official of the Civil Defence Department in Al Ain yesterday said carelessness on the part of the motorists could lead to financial loss and physical injury.
"Vehicles must be maintained properly, especially in the hot summer days, to prevent accidents," he said.
The Civil Defence reported two fire incidents on Wednesday in which a car and an earthmoving machine were destroyed.
Nobody was hurt in the accidents.