Technical Inspection of Used Cars

How to perform a mechanical check on a used car Staff

Written by Staff Published on 02.06.2008 13:42:23 (updated on 02.06.2008) Reading time: 6 minutes

Written by Ciaran Kelly
for The Kelly Report

Part 2

How to make a Techincal Inspection of Used Cars

In the second of a four part series, Ciaran Kelly will help Expats avoid the pitfalls and pratfalls of buying a used car in CR.

Today´s issue: how to perform a mechanical check on a car, especially if you aren´t a mechanic.

Mechanical Quality of Used Cars

According to the Dopravni Inspecktorat (Czech traffic police), 70% of all cars in CR have had some type of body or motor repair. The percentage is even higher for imported cars into CR.

Here are some tips on how to determine the technical quality of a used car

1—Use your eyes

Look for production plates, tags or stickers with service data. Many legitimate repair garages now actually marking/writing down either on the motor or on driver doors, the kms of their inspection. Use that and compare it with the kilometers on the odometer.

Also, run your finger along all the spaces between the panels, for example between the hood and fender. The spacing should be even, cars that have been smashed usually have spacing that is not equal. Try it on your car now. Run your finger along the space between hood and fender. It is easy, and you can´t be fooled. Do this on the hood, all doors, fenders and the trunk (boot)

Finally, ask to look under the hood (bonnet). Look at screws/bolts used to mount the motor to car frame. All those screws and bolts are painted by the factory. If any bolts are not painted, they have been taken out at some point in the car´s history.


Look closely under a florescent lamp or out in bright daylight. You will be able to see variations in paint color and shading and also graining in the paint itself if a car has had body work.
An old trick that still works, is to take out a large handkerchief, place it somewhere on the car body, then place a magnet in the middle of the kerchief. Drag the kerchief along the entire panel, if the magnet ever falls off, viola! The car has bonding and not metal, therefore it has been smashed.

3—Original Joints and Body Cementing

Open the hood and trunk; do not be afraid to remove all carpets, plastic covers and the spare wheel. You will be able to see the internal joints (welds) of the body frame. The joints are nowadays made exclusively by machines and robots, they should appear perfectly symmetrical, if not, the car has been severely smashed.


Closely look at fabric or leather of the seats. Small holes in seats means a smoker used the car. Leather and fabric will eventually crack and split, if so this means car probably has more than 130,000km on it.

Check the steering wheel. Most cars use a pilled or bumpy and grainy wheel grip. If this appears smooth in the classic „ten to two“ or „quarter to three“ positions of the steering wheel, you can bet the car has over 150,000km…maybe 200,000km.

Ditto the brake, clutch and accelerator pedals. They start to look smooth and worn down after 150,000km.

Beware of any car that has a smooth or dull looking stick shift, or if the material surrounding the stick shift is ripped or worn looking.

Cars usually do not show wear in any of these interior places until after the 80,000km mark

One last note on this…it doesn´t happen much these days, but after the floods of ‘02 some people tried dumping their flooded cars on the market. You can tell if a car has been flooded by removing the water lining of a side door (it is normally a black band used to keep rain out). Any difference in appearance of paint under the band will show clearly that car was submerged.


Common sense here will go a long way. Make sure all head, brake and interior lights, blinkers and control panel indicators actually function. Be wary of any headlamps that make a noise when turned on. If a car has A/C, also check that twice, once when the motor is off and once again during test drive.


Very under rated source of safety issues can be found here. Only experts can look at a tire and determine how many km´s are on it. But you can look to see if the tire wear is even. If not, for example the inside is wearing faster than outside of tire, this tells you there may be a problem with alignment or worse, something is amiss with the axle, shocks or suspension.


One dirty trick the importers are using these days:

Turn the key to first position. All indicator lights on the dash board go on (including airbag light). These should all turn off gradually…I repeat gradually turn themselves off. If all of them go off together at once, or if the airbag light goes off with another light at same time, that means the airbag light switch has been re-connected to another fuse. The airbags have, in fact, been blown already. Car has been severely smashed. On a car with perfectly functional airbags, the air bag light should be the last remaining dash board light to turn itself off after you start ignition.

You can also look closely to airbag position in the dash board itself. Just like point 1 above, run your finger over the spacing between airbag location and cover, the spacing should be perfectly even…any gap increase or decrease should tell you that air bag is blown.

On steering wheels, place your finger right in the middle of the steering wheel and push hard. It should feel like a solid wall to you, if the steering wheel “pushes” in, the airbag is not there. Also, AIRBAG or AIRBAG – SRS should be written on the steering wheel. If not, the steering wheel is not original.


Same as earlier, open hood/bonnet and look closely at the bolts/screws. Before starting the motor, open the water tank and place your finger into the water, then remove your finger. If your finger is dirty or black, oil is leaking because the sealing behind the heads is cracked. The motor should look clean and dry, it is not a disaster if the motor is dirty, but if you spot OIL on it, then you will have trouble

The engine should start simply by turning the key. Do not trust any engine which needs to step on the accelerator to start. Engine should start immediately. Focus on its operation; leave it running at a standstill. Listen for knocking sounds also take notice if car oscillates, that is increases or decreases rpm´s on its own. Remove oil cover and smell it. If you smell gasoline/diesel, there is a leak in fuel pumps.

After a ten minute test drive look for the mechanics stop light: Black, Blue and White. Keep the motor running and look closely at exhaust (you don´t have to smell it!) If you see blue smoke, piston rings let in oil in the cylinder, or the valves are leaking, in either case the engine is heavily worn out. If you see black smoke (with a diesel) the engine is worn and probably has a bad fuel pump. If you see white smoke, water is leaking in the cooling system, it may be a poor sealing or a broken head.


About the author

Ciaran Kelly has been a member of since 2005. He is Group Marketing Director and International Sales and Operations Controller for AAA AUTO. He has lived in CR since 1993, is married and has three children. He is a University teacher of history, politics and business classes, and also coaches American Football (4 times as national champion Prague Panthers, and now for the newly formed Pilsen Patriots)

He can be reached at or at +420 725 559 820


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