Batteries & Diagnostic Tools

If you are interested in auto mechanics, the first thing you need to know is what sort of basic equipment you will need.

A home mechanic will probably not need the same level of equipment as a professional, but there are a few things that you should definitely invest in before you get started.

Even if you aren’t able to fix a problem, being able to diagnose exactly what is going wrong is always going to be of benefit to you.

An engine code reader is essentially a diagnostic tool you use to find out what the problem is. So, if an engine warning light comes on, it could be a wide number of things from changing the oil to something much more serious. An engine reader will allow you to diagnose the problem at home and then, if you know what you are doing and have the right tools, you have the chance to deal with the problem yourself. All you need to do is plug in your code reader and then look up the relevant code to see what is wrong. To help you get started we compiled this list of the best car diagnostic tools.

Compression Testers

A compression tester is another diagnostic tool that can come in really useful. A compression tester is used to check the compression in each of your engines cylinder. This will give you a more accurate view of what is going wrong in the engine and where the problem lies. Many people ignore engine issues in the hope that they will go away on their own, but with a compression tester, you will be able to see what the problem is and either fix it yourself or take it to your mechanic.

Spark Plug Testers

A spark plug tester is used to determine whether there is a strong enough electrical signal reaching the engine. The tester is very easy to operate and is a safe way to check a signal. All you have to do is remove the HT lead and plug in your spark plug tester so that it forms an in-line connection to the end of the HT lead and the spark plug base. Turn on the engine as usual and the tester should illuminate as long as it is receiving a strong electrical input. If the light doesn’t come on, you will need to work your way down the ignition system to find the problem.

12v Test Light

A 12V test light is the best tool for figuring out where an electrical short is. It is very easy to use and is safe too. All you need to do is ground your test light to the negative terminal on your car battery. As long as your light works, you can use it to go around your car to find where an electrical fault lies. You should have a wiring schematic by your side to make testing fuses simpler and so that you can diagnose a problem straight away.

Timing Light

If you have ever been driving along and suddenly your car starts shaking and shuddering, you have probably panicked and thought that this must be the end for your vehicle. However, a car timing light can be used to diagnose the problem which might be a simple case of your spark plug not quite firing at the optimum time. There are a few different kinds of timing light you can use but the basic models will be fine for most things. Check your results against the proper timing specifications which can be found on a sticker under the car hood or in your user manual.

Mechanic’s Stethoscope

Much like a doctor’s stethoscope, a mechanic’s stethoscope is used to diagnose issues by listening closely to narrow down where an odd sound is coming from. Lots of mechanical issues can be isolated in this way and given that it is a cheap and safe option, the mechanic’s stethoscope is one of your best tools.

There two main advantages to the stethoscope that you might not have thought of: firstly, the stethoscope dampens the sound so that it is more comfortable for your ears; secondly, the stethoscope makes it much easier and safer to listen to hard-to-reach areas.

Vacuum Gauge

A vacuum gauge is the easiest way to find out whether an engine is healthy or not. If you are not familiar with the process, you are well advised to test out a few healthy cars with your vacuum gauge first so that you can see what the differences are with your unhealthy engine.

A vacuum gauge is also a good tool to have handy if you are planning to modify your engine because it will show whether your engine is in good enough condition or not by telling you whether it is reaching its stock horsepower. If your engine isn’t reaching this number, you should rethink your plans! Your vacuum gauge can also be used to diagnose a sticky valve, a burnt valve, worn valve guides, weak valve springs, or a vacuum leak.

Fuel Pressure Gauge

A fuel pressure gauge is used to monitor the pressure of fuel while you are driving. This is a great diagnostic tool to have as it is easy to install and use. To choose the best fuel pressure gauge, you will first need to find out what kind of fuel pump you are using so that you can get a complementary gauge.

Your fuel pressure gauge is also a useful tool for making your car more environmentally friendly by monitoring the emissions and gases released. You will naturally become more aware of your fuel consumption and be encouraged to be more conservative when you drive.


Here is a YouTube video that gives an overview of useful diagnostic tools for mechanics:

With these tools, you will find that you become much more familiar with your car and its particular quirks. You will also be able to do more diagnostic tests at home, saving you a lot in mechanic’s bills. Even if you cannot fix an issue yourself, being able to tell your mechanic exactly what the problem is will save you time and money.