When you’re looking at a used car to buy and you bring it to your mechanic for an inspection, are there any certain routine checks (to the engine specifically) that the mechanic does to the car? If so, would someone please list a basic check list of these procedures and how one might go about checking the engine themselves.
There are web sites that help, such as
http://www.consumerreports.org/main/detailv2.jsp?CONTENT<>cnt_id=113333&FOLDER<>folder_id=113261
You might not get the link, so just Google for “inspecting a used car’s engine” or “inspecting a used car.” I like the info. in the above link. Also look at the title to see if it mentions “salvage title.” Another topic. Good luck!
I do used car inspections. The idea is to find detectable repair and maintenance needs, and to get a general idea of how well the car has been maintained. Typically I write it up as “Used car inspection, inc. check belts, hoses, state of tune, fluids, steering, suspension, brakes, exhaust, lights, wipers, etc.” I don’t list out every single detail, some of which vary with different vehicle designs.
As far as the engine proper, it is not directly inspected. A test drive is part of the process, to check engine performance and transmission operation. If the engine runs well and there is no obvious smoke from the tailpipe or unsettling noise, there is no suspicion of internal engine problems.
Sometimes more can be learned from a properly done compression test. This would typically cost as much as the used car inspection above, more on some engines. My experience is that it’s rare to get poor compression test results on a good-running engine that has no symptoms of trouble. I sometimes use a compression test as a diagnostic aid when there is a performance problem, but I can’t say I’ve seen much point in doing it on an engine that seems to work fine. The exception to that would be on a very high-mileage vehicle–but most of them need hundreds or thousands of dollars worth of repairs discovered just from the overall inspection, making further inspection moot.
Now, if the engine is running poorly, it might be as simple (and relatively inexpensive) as needing some basic tune-up related maintenance, or it might be that a major–and majorly expensive–repair is needed. To find out, appropriate testing and/or repairs would have to be done, until the point is reached where either the problem is solved or it is apparent what the problem is. This almost always involves a lot more money than anyone wants to–or should–invest in a car they don’t own yet.
Gary T, why can’t you work where I take my car? (sigh)
Great to get a straight answer from a mechanic.
Thanks!
Here’s an old mechanic’s trick I learned from NPR’s Car Talk. Disconnect the wire that feeds the ignition coil. Then try to start the car. It won’t start, of course, but you’re listening to the cranking. If it’s even, the compression is more or less the same in all cylinders. If it’s uneven, there’s one or more cylinders with much lower compression. Don’t buy that one. It’s expensive to fix.