The Best Inspection Checklists!

Engine Checklist

When buying a used car the engine should probably be the single most important thing on your checklist. This is because it is very expensive to fix if damaged. Even if it’s not damaged but just worn out you still do not want to buy the car obviously. This brings up many questions as to how to test the engine of a used car. There is no simple answer to this question and there is no guarantee that the used car engine will last long. What we can achieve is to eliminate some obvious things and drastically improve our chances of finding a good car. This brings us to our used car engine checklist. (I should also mention that it is mostly applicable to petrol engines)

  1. First of all make sure the car is absolutely cold and has not been started or warmed up, this can cover-up some of the problems. So if you can pay a surprise visit and request a to see the car that way it is to your advantage.
  2. So now that the car is cold and we can start it you want someone to start up the car and give it some throttle (4500 rpm is fine). At this stage you should be looking at the exhaust pipe for different colors smoke. In general you should not see white , blue or black smoke. A bit is ok, but the less the better. White smoke can indicate that the car is burning coolant. Blue smoke indicates that the car is burning oil. Black smoke indicates that the car is maybe running rich. For now just keep in mind less smoke is better.
  3. Now that we hopefully saw no smoke on start-up we have to look under the bonnet and remove the oil cap. There should be no white residue on the oil cap.
  4. Upon removal of the oil cap the engine should preferably not change in sound or rpm. Ideally it would keep running as if nothing had happened. If sucks in a lot of air or even stalls it’s not a good sign.
  5. Now with the oil cap removed, if someone gives the car some gas you want to see that there is no steam coming our of the engine, or you could place the cap gently on it’s place without tightening it, if the car dances or even falls off that’s a bad sign. Ideally it should not move at all.
  6. Now you can put the oil cap back in place and pull out the oil stick. Again there should be no change in idle and no white reside on the oil stick.
  7. You can wipe a bit of oil from the stick between you fingers and you should not feel any small particles.
  8. Now put the oil stick in it’s place and very very carefully remove the coolant cap. Since the engine is cold there should be no problem, but still be ultra careful with this step. When the car warms up pressure builds up in the cooling system and opening the cap can cause coolant to spray you and burn you causing damage, so please be very careful. When the coolant cap is off inside the coolant should be clean and clear. No residue should be present. Now if someone gives the car some gas make sure there are no bubbles coming out. This does not necessarily indicate a problem but preferably there should be no bubbles.
  9. Find out if the car has a timing belt or chain and ask when it has been changed, and if there is documentation on it. If it has a timing belt I strongly suggest that you change if you buy the car. And when you do, pick a reputable mechanic and safe the invoice should something go wrong.
  10. Finally you can listen to the engine at different rpm levels for some unusual noises. Preferably no unusual noises should be detected.
  11. Look around the engine bay for external oil leaks. We prefer to have no such leaks around.
  12. Look at the engine parts of some hand written numbers or stickers with handwritten text or numbers. This indicates probably that the part you are looking at has been changed and has been bought from a car morgue. You can ask the owner or dealer what has happened.
  13. Finally don’t get too caught up on every small detail, if the car passed most of the points on our used car checklist you can ask a mechanic to perform a technical test on the car. This step is absolutely necessary and we strongly recommend it. Mechanics have better tools that can diagnose a car more accurately. If you found something during the check that seems off you can point the mechanic to that specific point from the checklist.
  14. As a bonus to our used car checklist I would add that performing a compression test on every cylinder could be a good thing to do , especially if the car is more expensive. However many sellers/dealers will not like the idea and might reject it. This is something the the mechanic can perform while doing the rest of the vehicle inspection.